# Black Mountain K4 South west Belfast. 661 people (mid-2024 estimate) in 0.1 square kilometres. Black Mountain K4 had 683 usual residents at the census (NISRA Census 2021). Neighbourhood. Code N20001339. In: [Northern Ireland](https://openindex.co.uk/northern-ireland) › [Belfast](https://openindex.co.uk/belfast) ## Key figures - **Population: 683** (2021). Black Mountain K4 had 683 usual residents at the census (NISRA Census 2021). Joint 6,483rd least populated of 46,844. Source: Census 2021, England and Wales and Scotland's Census 2022 and Census 2021, Northern Ireland, 2021. Published 21 July 2026. https://openindex.co.uk/belfast/neighbourhood/n20001339#f-population - **Gigabit broadband coverage: 100.0%** (January 2026). In Black Mountain K4, 100.0% of homes and businesses could get gigabit-capable broadband in January 2026 (Ofcom). UK 87.8%. Source: Connected Nations (Ofcom), January 2026. Published 13 May 2026. https://openindex.co.uk/belfast/neighbourhood/n20001339#f-gigabit-coverage - **Aged 15 to 64: 65.9%** (2021). 65.9% of residents in Black Mountain K4 were aged 15 to 64 at the census (NISRA Census 2021). Joint 14,926th highest of 46,844. Source: Census 2021, England and Wales and Scotland's Census 2022 and Census 2021, Northern Ireland, 2021. Published 21 July 2026. https://openindex.co.uk/belfast/neighbourhood/n20001339#f-age-15-to-64 - **Aged 65 and over: 22.3%** (2021). 22.3% of residents in Black Mountain K4 were aged 65 or over at the census (NISRA Census 2021). Joint 16,052nd highest of 46,844. Source: Census 2021, England and Wales and Scotland's Census 2022 and Census 2021, Northern Ireland, 2021. Published 21 July 2026. https://openindex.co.uk/belfast/neighbourhood/n20001339#f-age-65-and-over ## On the map - [Gigabit coverage by neighbourhood](https://openindex.co.uk/map/gigabit-broadband?place=N20001339) (Connected Nations (Ofcom) · January 2026): In Black Mountain K4, 100.0% of homes and businesses could get gigabit-capable broadband in January 2026. - [Average house price by council](https://openindex.co.uk/map/house-prices?place=N20001339) (UK House Price Index · August 2026): Published for whole councils, so the map colours all of Belfast. The outline is Black Mountain K4. - [Crime and ASB by neighbourhood](https://openindex.co.uk/map/recorded-crime?place=N20001339) (Police recorded crime and outcomes (data.police.uk) · August 2026): Police recorded 1 crime or anti-social behaviour incident in Black Mountain K4 in August 2026. - [Population by neighbourhood](https://openindex.co.uk/map/population?place=N20001339) (Census 2021, England and Wales): Black Mountain K4 had 683 usual residents at the census. Northern Ireland Multiple Deprivation Measure 2017 is published for the Super Output Areas (2001), whose boundaries differ from this neighbourhood’s, so it has no figure for Black Mountain K4. [See deprivation across Belfast](https://openindex.co.uk/belfast/deprivation) ## How Black Mountain K4 compares Each neighbourhood against every other neighbourhood the measure covers. | Measure | Black Mountain K4 | Rank | Compared with | | --- | --- | --- | --- | | Population | 683 | 47th most populated | 735 neighbourhoods, Belfast · 2021 | | Gigabit broadband coverage | 100.0% | joint highest | 735 neighbourhoods, Belfast · Jan 2026 | | Aged 15 to 64 | 65.9% | joint 334th highest | 735 neighbourhoods, Belfast · 2021 | | Aged 65 and over | 22.3% | joint 101st highest | 735 neighbourhoods, Belfast · 2021 | ## Is Black Mountain K4 safe? What police records show In the 12 months to August 2026, police recorded crimes and anti-social behaviour in Black Mountain K4 at a rate of 48.4 per 1,000 people. That compares with 88.0 per 1,000 people across Black Mountain K. Across Northern Ireland as a whole, the recorded crime rate was 70.2 per 1,000 people. In August 2026 alone, 1 case of crime and anti-social behaviour was recorded in Black Mountain K4. In the 12 months to August 2026, the most common types were violence and sexual offences (20), anti-social behaviour (7) and other crime (2). Worked out by Open Index from police.uk crime records and ONS and NISRA population estimates. Rates are per resident, so places that many people work in or visit, such as Westminster, the City of London and other city centres, have far higher rates than their residents alone would suggest. ## Figures for the whole of Belfast These figures are published for the whole of Belfast, not for each neighbourhood, so they describe all of Belfast and not Black Mountain K4 alone. [See Belfast](https://openindex.co.uk/belfast) - **Average house price: £184,768** (August 2026). Belfast’s average house price was £184,768 in August 2026 (HM Land Registry). Up 7.7% in a year. Source: UK House Price Index, August 2026. Published 21 October 2026. - **Population estimate: 351,927** (2025). Belfast’s population was an estimated 351,927 in mid-2025 (ONS population estimates). Down 0.1% in a year. Source: Mid-year population estimates, 2025. Published 1 October 2026. - **Female life expectancy: 80.5 years** (2022 to 2024). A baby girl born in Belfast could expect to live 80.5 years, based on deaths in 2022 to 2024 (ONS life expectancy). UK 83.0 years. Source: Life expectancy for local areas of the UK, 2022 to 2024. Published 10 December 2025. - **People in radon Affected Area squares: 14%** (2022). About 14% of people in Belfast live in a 1 km square that the radon atlas marks as a radon Affected Area. UK 44%. Source: Worked out by Open Index from the UKHSA and BGS radon atlas and census output areas. Published 1 December 2022. ## Black Mountain K4 in brief Black Mountain K4 had 683 usual residents at the census. In Black Mountain K4, 100.0% of homes and businesses could get gigabit-capable broadband in January 2026. 65.9% of residents in Black Mountain K4 were aged 15 to 64 at the census. 22.3% of residents in Black Mountain K4 were aged 65 or over at the census. ## About - Type: Neighbourhood - Code: N20001339 - Middle area: [Black Mountain K](https://openindex.co.uk/belfast/black-mountain-k) - Ward: [Shaw's Road †](https://openindex.co.uk/belfast/ward/shaws-road) - Constituency: [Belfast West †](https://openindex.co.uk/constituency/belfast-west) - Council: [Belfast](https://openindex.co.uk/belfast) - Nation: [Northern Ireland](https://openindex.co.uk/northern-ireland) - Area: 0.14 km² - People, mid-2024: 661 † Best fit: the ward and constituency this neighbourhood mostly lies in. Its edges do not follow theirs. ## Next door [Black Mountain N1](https://openindex.co.uk/belfast/neighbourhood/n20001343), [Black Mountain L1](https://openindex.co.uk/belfast/neighbourhood/n20001342), [Black Mountain H2](https://openindex.co.uk/belfast/neighbourhood/n20001328), [Black Mountain L3](https://openindex.co.uk/belfast/neighbourhood/n20001352), [Black Mountain K1](https://openindex.co.uk/belfast/neighbourhood/n20001332), [Black Mountain K2](https://openindex.co.uk/belfast/neighbourhood/n20001335) ## Latest updates for Black Mountain K4 - August 2026 house prices published: HM Land Registry and partners · Oct 2026. - September 2026 rent published: ONS private rents · Oct 2026. - Nitrogen dioxide (NO2) updated: Defra · Oct 2026. - 2025 population published: ONS population estimates · Oct 2026. The same figures as JSON: https://openindex.co.uk/v1/places/N20001339 ## How to cite Source: Open Index, openindex.co.uk. Link to this page, https://openindex.co.uk/belfast/neighbourhood/n20001339, or to one figure with its anchor, https://openindex.co.uk/belfast/neighbourhood/n20001339#f-population. Open Index's own text and the figures it works out are licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source data keeps its publishers' licences, named with each figure. Give each figure's period and source with it. Snapshot 2026.10.9. The HTML page: https://openindex.co.uk/belfast/neighbourhood/n20001339