Silvermere Road Catford, Lewisham
117 addresses across 4 postcodes (SE6), about 410 m (0.3 miles) long, classed as a local road. USRN 22001896.
- Sales: 132 recorded sales since 1995; in 2026 the median was £525,000 across 1 sale.
- Energy: 72 homes have an energy certificate (B: 2, C: 22, D: 37, E: 10, F: 1).
- Flood: 17 addresses on its postcodes are in areas at high or medium risk of flooding from rivers, the sea or surface water.
- Council tax: Most homes around it are in council tax band C; Band D in Lewisham costs £2,237 a year in 2026-27.
- Broadband: Gigabit broadband is available to 100% of premises.
- Transport: The nearest railway station is Catford Bridge, about 410 m (0.3 miles) away in a straight line.
- Green space: The nearest park or garden, Ladywell Fields, is about 260 m away.
- Air: Background air pollution in 2024 was 18.2 µg/m³ of nitrogen dioxide and 9.1 of PM2.5, within UK legal limits.
- Height: Its addresses are 14 to 16 m above sea level.
- Noise: 10 of its 117 addresses are modelled at 55 dB or more from road traffic.
- Doctors: The nearest GP surgery is Novum Health Partnership, about 310 m away, with 10 practices within 1.6 km (1 mile).
- People: About 890 people lived in the census areas around it in 2021; 54% of households owned their home and 44% of adults held a degree or other higher qualification.
- Crime: 532 crimes were recorded within 250 m between September 2025 and August 2026, most often violence and sexual offences.
Sales on this street
| Year | Sales | Median price | Lowest | Highest |
|---|---|---|---|---|
| 2026 | 1 | £525,000 | £525,000 | £525,000 |
| 2025 | 2 | £410,000 | £325,000 | £495,000 |
| 2024 | 2 | £554,500 | £515,000 | £594,000 |
| 2023 | 1 | £776,250 | £776,250 | £776,250 |
| 2022 | 2 | £718,750 | £687,500 | £750,000 |
| 2021 | 2 | £533,500 | £527,000 | £540,000 |
| 2020 | 3 | £655,000 | £592,500 | £658,000 |
| 2018 | 5 | £498,500 | £426,000 | £663,000 |
| 2017 | 8 | £447,500 | £295,000 | £600,000 |
| 2016 | 2 | £376,500 | £313,000 | £440,000 |
| 2015 | 7 | £430,000 | £250,000 | £570,000 |
| 2014 | 3 | £445,000 | £335,000 | £567,000 |
| Date | Address | Type | Price | Notes |
|---|---|---|---|---|
| 26 Jun 2026 | 125 SE6 4QU | Terraced | £525,000 | |
| 21 May 2025 | 106B SE6 4QT | Semi-detached | £325,000 | |
| 7 Feb 2025 | 121 SE6 4QU | Terraced | £495,000 | |
| 2 May 2024 | 96 SE6 4QS | Terraced | £594,000 | |
| 15 Mar 2024 | 89 SE6 4QX | Terraced | £515,000 | |
| 19 Dec 2023 | 134 SE6 4QT | Terraced | £776,250 | |
| 3 Jul 2023 | 92 SE6 4QS | Terraced | £510,000 | Not a standard sale (repossession, buy-to-let or transfer). |
| 30 May 2023 | 97 SE6 4QU | Terraced | £500,000 | Not a standard sale (repossession, buy-to-let or transfer). |
| 10 Mar 2023 | 160 SE6 4QT | Flat or maisonette | £220,000 | Leasehold. Not a standard sale (repossession, buy-to-let or transfer). |
| 15 Nov 2022 | 133 SE6 4QU | Terraced | £750,000 | |
| 14 Feb 2022 | 144 SE6 4QT | Terraced | £687,500 | |
| 13 Apr 2021 | 101 SE6 4QU | Terraced | £540,000 | |
| 1 Mar 2021 | 117 SE6 4QU | Terraced | £527,000 | |
| 11 Dec 2020 | 93 SE6 4QX | Terraced | £592,500 | |
| 30 Oct 2020 | 116 SE6 4QT | Terraced | £658,000 | |
| 14 Oct 2020 | 76 SE6 4QS | Terraced | £655,000 | |
| 24 Sep 2018 | 118 SE6 4QT | Terraced | £498,500 | |
| 31 Aug 2018 | 141 SE6 4QU | Terraced | £663,000 | |
| 25 May 2018 | 78 SE6 4QS | Terraced | £510,000 | |
| 23 Mar 2018 | 75 SE6 4QX | Terraced | £445,000 | |
| 23 Feb 2018 | 96 SE6 4QS | Terraced | £426,000 | |
| 15 Dec 2017 | 46 SE6 4QS | Semi-detached | £450,000 | |
| 27 Nov 2017 | 106A SE6 4QT | Semi-detached | £407,000 | |
| 7 Nov 2017 | 93 SE6 4QX | Terraced | £557,500 | |
| 14 Jul 2017 | 64 SE6 4QS | Terraced | £600,000 | |
| 26 May 2017 | 71 SE6 4QX | Terraced | £408,000 | |
| 24 Apr 2017 | 85 SE6 4QX | Terraced | £460,000 | |
| 7 Apr 2017 | 39 SE6 4QX | Flat or maisonette | £295,000 | Leasehold. |
| 10 Mar 2017 | 116 SE6 4QT | Terraced | £445,000 | |
| 27 Jan 2017 | 93 SE6 4QX | Terraced | £415,000 | Not a standard sale (repossession, buy-to-let or transfer). |
| 4 Jul 2016 | 39 SE6 4QX | Flat or maisonette | £313,000 | Leasehold. |
| 30 Mar 2016 | 76 SE6 4QS | Terraced | £440,000 | |
| 30 Oct 2015 | 150 SE6 4QT | Terraced | £495,000 | |
| 16 Oct 2015 | 54 SE6 4QS | Terraced | £485,000 | |
| 2 Oct 2015 | 141 SE6 4QU | Terraced | £570,000 | |
| 18 Sep 2015 | 72 SE6 4QS | Terraced | £425,000 | |
| 7 Aug 2015 | 134 SE6 4QT | Terraced | £430,000 | |
| 15 Jan 2015 | 106B SE6 4QT | Semi-detached | £250,000 | New build. |
| 6 Jan 2015 | 79 SE6 4QX | Terraced | £379,000 | |
| 17 Nov 2014 | 156 SE6 4QT | Terraced | £445,000 | |
| 11 Jul 2014 | 144 SE6 4QT | Terraced | £567,000 | |
| 11 Jul 2014 | 120 SE6 4QT | Terraced | £335,000 | |
| 8 Mar 2013 | 106 SE6 4QT | Terraced | £302,500 | |
| 24 Aug 2012 | 98 SE6 4QS | Terraced | £280,000 | |
| 22 Mar 2012 | 64 SE6 4QS | Terraced | £245,000 | |
| 12 Dec 2011 | 39 SE6 4QX | Flat or maisonette | £165,000 | Leasehold. |
| 12 Dec 2011 | 39 SE6 4QX | Flat or maisonette | £157,000 | Leasehold. |
| 10 Oct 2011 | 138 SE6 4QT | Terraced | £205,000 | |
| 30 Sep 2011 | 139 SE6 4QU | Terraced | £330,000 | |
| 6 Apr 2011 | 144 SE6 4QT | Terraced | £265,000 |
Energy performance certificates
72 homes with a current certificate; median floor area 85 m². Most common: House, mid-terrace (46); House, end-terrace (12); Flat (9). Built: 1900-1929 (39); before 1900 (14); 1991-1995 (7). Tenure at assessment: owner-occupied (32); rented (private) (17); rented (social) (13).
Each home's certificates and sales (37 addresses)
- 39, Silvermere Road
- 42, Silvermere Road
- 44, Silvermere Road
- 46, Silvermere Road
- 50, Silvermere Road
- 64, Silvermere Road
- 72, Silvermere Road
- 75, Silvermere Road
- 76, Silvermere Road
- 78, Silvermere Road
- 79, Silvermere Road
- 83, Silvermere Road
- 85, Silvermere Road
- 87, Silvermere Road
- 89, Silvermere Road
- 96, Silvermere Road
- 98, Silvermere Road
- 99, Silvermere Road
- 103, Silvermere Road
- 105, Silvermere Road
- 106, Silvermere Road
- 106a, Silvermere Road
- 116, Silvermere Road
- 118, Silvermere Road
- 122, Silvermere Road
- 133, Silvermere Road
- 136, Silvermere Road
- 137 Silvermere Road
- 137a, Silvermere Road
- 137b, Silvermere Road
- 139, Silvermere Road
- 141, Silvermere Road
- 144, Silvermere Road
- 148, Silvermere Road
- 150, Silvermere Road
- 156, Silvermere Road
- 160, Silvermere Road
Council tax
What each band costs in Lewisham in 2026-27: Band D £2,237 a year on average, including the police, fire and any county and parish charges.
| A | B | C | D | E | F | G | H |
|---|---|---|---|---|---|---|---|
| £1,492 | £1,740 | £1,989 | £2,237 | £2,735 | £3,232 | £3,729 | £4,475 |
Homes by band in the neighbourhoods around this street: most are in band C (43% of about 1,110 homes).
Planning and heritage
- Conservation area: no postcode centre in this street's postcodes is in one.
- Listed buildings on or by this street: none.
- Article 4 direction (removing permitted development rights): Small HMO Northern Extension.
- Tree preservation orders: none recorded, though not every council has published theirs.
- Green belt: no.
Brownfield land registered for housing within 1 km (0.6 miles)
- Catford Shopping Centre and Milford Towers: up to 1,084 homes, permissioned (200 m)
- 96-102 Rushey Green: up to 7 homes, permissioned (200 m)
- Duke House, 84-86a Rushey Green: up to 6 homes, permissioned (230 m)
- Land at Rushey Green and Bradgate Road (Aldi): up to 88 homes, not permissioned (290 m)
- 83-85a Rushey Green: up to 9 homes, permissioned (320 m)
- Laurence House and Civic Centre: up to 262 homes, not permissioned (360 m)
- Catford Island: up to 602 homes, not permissioned (410 m (0.3 miles))
- 16-22 Brownhill Road, permissioned (440 m (0.3 miles))
Roadworks
No street works under way, planned or finished in the last three months on this street, in permits up to 31 October 2026.
Flood risk
Rivers, the sea or surface water: in this street's postcodes, 9 addresses are in areas at high risk, 8 at medium risk and 67 at low risk. Each address counts once, at the higher of its rivers-and-sea and surface-water risk.
Rivers and the sea alone: of the 113 homes the Environment Agency counts, 0 are in areas at high risk, 0 medium, 76 low and 0 very low.
High: 3.3% (1 in 30) or more chance of flooding a year. Medium: 1% to 3.3%. Low: 0.1% to 1%. Very low: under 0.1%. The rivers and sea figures allow for flood defences. Counts cover whole postcodes, which can include other streets.
Flood zone for planning: at least one postcode centre is in flood zone 2. Zone 2 is between 0.1% and 1% a year from rivers (0.1% and 0.5% from the sea), ignoring defences.
| Postcode | Planning zone | Addresses at high / medium / low risk | Groundwater |
|---|---|---|---|
| SE6 4QT | zone 2 | 9 / 3 / 18 | unlikely |
| SE6 4QX | zone 2 | 0 / 3 / 7 | unlikely |
| SE6 4QS | zone 2 | 0 / 0 / 21 | unlikely |
| SE6 4QU | zone 2 | 0 / 2 / 21 | unlikely |
Height above sea level
The street's 117 addresses are between 14 m and 16 m above sea level (15 m on average).
Broadband
| Postcode | Superfast (30 Mbit/s+) | Ultrafast (300 Mbit/s+) | Gigabit | Below 10 Mbit/s |
|---|---|---|---|---|
| SE6 4QS | 100% | 100% | 100% | 0% |
| SE6 4QT | 100% | 100% | 100% | 0% |
| SE6 4QU | 100% | 100% | 100% | 0% |
| SE6 4QX | 100% | 100% | 100% | 0% |
Getting around
| Nearest | Distance | |
|---|---|---|
| Railway stations | Catford Bridge 2.5 million journeys in 2024–25 | 410 m (0.3 miles) |
| Catford 777,000 journeys in 2024–25 | 500 m (0.3 miles) | |
| Ladywell 1.3 million journeys in 2024–25 | 940 m (0.6 miles) | |
| Underground, metro or tram | Lewisham DLR Station | 2 km (1.2 miles) |
| Bus stops | 14 stops within 400 m (0.2 miles), 46 within 800 m (0.5 miles); nearest Thomas Lane Catford | 190 m |
| Bus or coach station | West Dulwich - Croxted Road | 5 km (3.1 miles) |
| Ferry terminal | Greenwich Pier | 4.1 km (2.5 miles) |
| Car parks | Sainsbury's Sydenham Car Park | 2.2 km (1.4 miles) |
| EV charging points | 33 within 1.6 km (1 mile); nearest MFG Charging Station | 640 m (0.4 miles) |
| Airport with scheduled flights | London City Airport LCY | 8.3 km (5.2 miles) |
| Nearest large airport | London Heathrow Airport LHR | 30.5 km (19 miles) |
Local services
| Nearest | Distance | |
|---|---|---|
| GP surgeries | 10 practices within 1.6 km (1 mile); nearest Novum Health Partnership | 310 m |
| Pharmacies | 9 pharmacies within 1.6 km (1 mile); nearest Superdrug Pharmacy | 250 m |
| NHS dentists | 10 practices within 1.6 km (1 mile); nearest The Broadway Dental Practice | 270 m |
| Hospital | University Hospital Lewisham | 630 m (0.4 miles) |
| Police station | Catford Police Base | 1.2 km (0.7 miles) |
| Cash machines | 3 machines within 800 m (0.5 miles); nearest Payzone | 270 m |
Parks and green space
| Nearest | Distance | |
|---|---|---|
| Park or garden | 6 within 800 m (0.5 miles); nearest Ladywell Fields 19 ha | 260 m |
| Play area | 7 within 800 m (0.5 miles); nearest Unnamed 1,050 m² | 350 m |
| Playing field | 1 within 800 m (0.5 miles); nearest Unnamed 3,510 m² | 760 m (0.5 miles) |
| Allotments | 1 within 800 m (0.5 miles); nearest Unnamed 4,270 m² | 800 m (0.5 miles) |
Within 800 m (0.5 miles): 6 parks and gardens, 39 hectares in all.
Landmarks
The nearest historic landmark is Church of St Mary the Virgin, a listed building (Grade II*), 1 km (0.6 miles) north-east. 13 listed buildings are within 1 km (0.6 miles), 1 of them Grade II*.
| Name | What it is | From the middle of the street |
|---|---|---|
| Church of St Mary the Virgin | Listed building, Grade II* | 1 km (0.6 miles) north-east |
| Manor House Gardens | Registered park or garden, Grade II | 2.1 km (1.3 miles) north-east |
| Nunhead Cemetery (All Saints) | Registered park or garden, Grade II* | 2.6 km (1.6 miles) north-west |
| Maritime Greenwich | World Heritage Site | 3.7 km (2.3 miles) north |
| Name | What it is | From the middle of the street |
|---|---|---|
| Devonshire Road Nature Reserve | Wood | 1.9 km (1.2 miles) west |
| Honor Oak | Wood | 2.1 km (1.3 miles) west |
| Oak of Honor Hill | Hill | 2.1 km (1.3 miles) west |
| Folly Pond | Lake or reservoir | 3.2 km (2 miles) north-east |
| Greenwich Reach | Tidal water | 4.2 km (2.6 miles) north |
| Saunders Ness | Wetland | 4.9 km (3.1 miles) north |
Air quality
| Pollutant | Here | UK limit | WHO guideline |
|---|---|---|---|
| Nitrogen dioxide (NO2) | 18.2 | 40 | 10 |
| Fine particles (PM2.5) | 9.1 | 20 | 5 |
| Particles (PM10) | 15.2 | 40 | 15 |
All three are within the UK legal limits; all three are above the WHO guideline, as in most towns and cities.
Road and rail noise
| Level | Road traffic | Railways |
|---|---|---|
| 60 to 64 | 5 | 1 |
| 55 to 59 | 5 | 2 |
| Under 55 | 107 | 114 |
10 of the street's 117 addresses are modelled at 55 dB or more from road traffic, and 3 from railways, above the WHO guidelines.
Climate, daylight and earthquakes
Monthly temperatures and rainfall, sunrise and sunset through the year, and earthquakes recorded nearby since 1970 are much the same across the area, so they are worked out once for Lewisham: see them on the Lewisham page.
Nearest schools
| School | Phase | Ages | Distance | Inspection |
|---|---|---|---|---|
| Holbeach Primary School | Primary | 3–11 | 90 m | No published inspection |
| Prendergast Ladywell School | All-through | 4–16 | 440 m (0.3 miles) | No published inspection |
| Rushey Green Primary School | Primary | 3–11 | 600 m (0.4 miles) | Good (Nov 2022, overall grade under the previous framework) |
| Holy Cross Catholic Primary School Roman Catholic | Primary | 3–11 | 680 m (0.4 miles) | No published inspection |
| St Mary's Lewisham Church of England Primary School | Primary | 3–11 | 920 m (0.6 miles) | Report card (Apr 2026): Curriculum and teaching: Strong standard; Achievement: Strong standard; Attendance and behaviour: Strong standard; Personal development and wellbeing: Strong standard; Inclusion: Strong standard; Leadership and governance: Strong standard; Early years: Strong standard; Safeguarding standards: Met |
| Gordonbrock Primary School | Primary | 3–11 | 1 km (0.6 miles) | No published inspection |
| Rathfern Primary School | Primary | 2–11 | 1.1 km (0.7 miles) | Report card (Jan 2026): Curriculum and teaching: Strong standard; Achievement: Expected standard; Attendance and behaviour: Strong standard; Personal development and wellbeing: Strong standard; Inclusion: Strong standard; Leadership and governance: Strong standard; Early years: Strong standard; Safeguarding standards: Met |
| Stillness Junior School | Primary | 7–11 | 1.2 km (0.7 miles) | Good (Feb 2020, overall grade under the previous framework) |
| Stillness Infant School | Primary | 3–7 | 1.2 km (0.7 miles) | Report card (Jul 2026): Curriculum and teaching: Strong standard; Achievement: Strong standard; Attendance and behaviour: Strong standard; Personal development and wellbeing: Strong standard; Inclusion: Strong standard; Leadership and governance: Strong standard; Early years: Strong standard; Safeguarding standards: Met |
| St William of York Catholic Primary School Roman Catholic | Primary | 3–11 | 1.3 km (0.8 miles) | Good (Oct 2022, overall grade under the previous framework) |
| Brindishe Green School | Primary | 3–11 | 1.3 km (0.8 miles) | Good (Sep 2023, overall grade under the previous framework) |
| Prendergast School | Secondary | 11–18 | 1.3 km (0.8 miles) | No overall grade (Mar 2025, graded inspection without an overall judgement): Quality of education: Outstanding; Behaviour and attitudes: Outstanding; Personal development: Outstanding; Leadership and management: Outstanding |
Food hygiene ratings nearby
| Business | Type | Distance | Rating | Rated |
|---|---|---|---|---|
| Brook Food & Wine SE6 4JP | Retailers - other | 50 m | 4 Good | 7 Nov 2025 |
| Olive Dining Ltd at Holbeach Primary School SE6 4TP | School/college/university | 60 m | 5 Very good | 9 Oct 2026 |
| Holbeach Baptist Church SE6 4JP | Restaurant/Cafe/Canteen | 120 m | 1 Major improvement necessary | 27 Mar 2026 |
| My Fathers Prophetic Ministries SE6 4HU | Restaurant/Cafe/Canteen | 120 m | 5 Very good | 13 Mar 2025 |
| Okans FOundation SE6 4HU | Distributors/Transporters | 120 m | 5 Very good | 26 Jun 2025 |
| Sam Grocers Ltd SE6 4TW | Retailers - other | 140 m | 4 Good | 26 Sep 2025 |
| Lee's Foodstore SE6 4JN | Retailers - other | 150 m | 5 Very good | 31 Oct 2025 |
| Q Stix SE6 4HW | Restaurant/Cafe/Canteen | 190 m | 2 Improvement necessary | 24 Feb 2025 |
| Catford Fairytop SE6 4HW | Pub/bar/nightclub | 190 m | 5 Very good | 8 Jun 2023 |
| Nandos SE6 4HW | Restaurant/Cafe/Canteen | 210 m | 5 Very good | 11 Sep 2025 |
| Poundland SE6 4HW | Retailers - other | 210 m | 5 Very good | 27 Oct 2025 |
| Z & K Butchers Catford Food Store SE6 4HW | Retailers - other | 210 m | 1 Major improvement necessary | 17 Sep 2025 |
| The Black Cat ( Catford Ram SE6 4JU | Restaurant/Cafe/Canteen | 210 m | 5 Very good | 14 Oct 2026 |
| Card Factory SE6 4JU | Retailers - other | 210 m | 5 Very good | 24 Oct 2025 |
| Iceland SE6 4JU | Retailers - supermarkets/hypermarkets | 220 m | 4 Good | 22 Oct 2025 |
Crime within 250 m
| Category | Crimes |
|---|---|
| Violence and sexual offences | 170 |
| Anti-social behaviour | 94 |
| Drugs | 51 |
| Other theft | 48 |
| Robbery | 32 |
| Shoplifting | 32 |
| Public order | 27 |
| Vehicle crime | 21 |
| Burglary | 16 |
| Criminal damage and arson | 12 |
| Theft from the person | 11 |
| Possession of weapons | 7 |
| Bicycle theft | 6 |
| Other crime | 5 |
Most of these are attached to: On or near Rushey Green (109); On or near Supermarket (103); On or near Parking Area (44); On or near Doggett Road (40); On or near Silvermere Road (39).
People and work
Who lives here
| Around this street | England | |
|---|---|---|
| Median age | 38 | 40 |
| Children under 15 | 18% | 17% |
| Aged 65 and over | 10% | 18% |
Homes
| Around this street | England | |
|---|---|---|
| Owned (outright or with a mortgage) | 54% | 61% |
| Owned outright | 23% | 33% |
| Shared ownership | under 1% | 1% |
| Social rented | 18% | 17% |
| Private rented | 27% | 21% |
Work and commuting
| Around this street | England | |
|---|---|---|
| Adults (16 and over) in work | 63% | 57% |
| Unemployment (of those working or looking for work) | 9% | 6% |
| Retired (of adults) | 11% | 22% |
| Long-term sick or disabled (of adults) | 6% | 4% |
| Work mainly from home (of those in work) | 43% | 32% |
| Travel to work by car or van | 20% | 48% |
| By train, Underground, metro or tram | 14% | 4% |
| By any public transport, including bus | 26% | 8% |
| On foot or by bicycle | 10% | 10% |
| Work within 10 km (6 miles) of home (of those who travel to work) | 78% | 65% |
| Work 30 km (19 miles) or more away | 3% | 8% |
Education and languages
| Around this street | England | |
|---|---|---|
| Degree or other higher qualification, Level 4+ (of adults) | 44% | 34% |
| No qualifications | 17% | 18% |
| Apprenticeship as highest qualification | 2% | 5% |
| Main language English (aged 3 and over) | 82% | 91% |
| Cannot speak English well or at all | 4% | 2% |
Deprivation
The 2 neighbourhoods around this street are in deciles 3 to 4 of 10 on the English Indices of Deprivation 2025, where 1 is the most deprived tenth of England's 33,755 neighbourhoods and 10 the least.
What has changed
Nothing new since the change feed started on 30 October 2026. New sales and energy certificates, and hygiene ratings, school inspections and flood figures nearby, will be listed here as the sources update.
Postcodes on this street
- SE6 4QT: 33 addresses
- SE6 4QX: 29 addresses of 30 in the postcode
- SE6 4QS: 28 addresses
- SE6 4QU: 27 addresses of 28 in the postcode
Nearby streets
Brookdale Road · Holbeach Road · Lamington Mews · Morena Street · Scrooby Street · Hamlet Close · Hawstead Road · Wildfell Road · Rushey Green · Bradgate Road · Doggett Road · Nelgarde Road
What this page cannot tell you
- Whether a particular house is at risk of flooding, subsiding or anything else: the flood map is a model of areas and there is no property-level data here.
- What a home is worth now: sales are historic prices for the homes that happened to sell.
- How safe the street is: crime points are moved to anonymised locations and many crimes are never reported.
- Whether you would get a place at a school: distances are straight lines, not catchments.
- Who lives on the street now: census figures describe the small areas around it in March 2021, during a lockdown.
- How long a journey takes or how often anything runs: transport distances are straight lines to the nearest stops.
- Whether a GP practice is taking new patients, or a dentist new NHS patients.
- How loud a home is inside, or noise from industry, neighbours or smaller airfields: noise figures are models of road, rail and air traffic outside.
How each figure on this page is matched to the street and worked out: methodology.