Cardiff's serious collisions, ward by ward
210 people were killed or seriously injured on Cardiff's roads over 2021–2025, 12 of them fatally. We mapped all 181 collisions to their council ward. Half of them happened in just 9 of the city's 28 wards.
The short answer
Serious road injury in Cardiff is concentrated, not spread. Cathays alone recorded 17 serious or fatal collisions in five years, more than the ten safest wards put together (27). Collisions track the road network rather than population: the A48, M4 and A4232 run through most of the worst-affected wards. And the direction of travel is wrong, with the city total up 3% since 2021.
Every figure here comes from the Department for Transport’s STATS19 records, the police record of injury collisions, point-matched to current ONS ward boundaries. Slight-injury collisions are excluded: this counts people killed or seriously injured (KSI). Full method.
Serious and fatal collisions by ward, 2021–2025
Darker means more people hurt. Click any ward for its numbers, and zoom in to see every individual serious (blue) and fatal (red) collision inside the ward boundary, so you can point at the exact junctions and corridors.
Five findings from 181 serious collisions
1. Half the city’s serious injuries happen in a quarter of its wards
9 of Cardiff’s 28 wards account for half of every serious and fatal collision in the city. The five worst (Cathays, Penylan, Plasnewydd, Riverside, Whitchurch and Tongwynlais) carry 62 between them, which is 34% of the total from 18% of the wards. At the other end, the 14 wards making up the safer half record 48 between them.
2. The trend is going the wrong way
Serious and fatal collisions rose from 37 in 2021 to 38 in 2025, a change of +3% across the period, peaking at 41 in 2023. Traffic volumes recovering after 2021 explain part of any rise, but not all of it on roads whose layout has not changed.
Serious and fatal collisions across Cardiff, per year
2025: 38 (up 52% on the year before) · peak 41 in 2023 · +2.7% across the period
Axis clipped to the data range to show year-on-year movement.
3. One road runs through the problem: the A48
Counting every ward it passes through, the A48 accounts for 16 serious and fatal collisions across 10 separate wards. A corridor-wide approach would reach more people than any single junction scheme.
Counts the first road recorded on each collision, so collisions on unclassified roads are absent from this table but included in ward totals.
4. Volume and lethality are different problems
Cathays records the most serious collisions in Cardiff (17), but 18 wards recorded no fatal collision at all in five years. Speed is usually what separates the two groups: outer wards see fewer collisions, at higher speeds, with worse outcomes.
Every ward, ranked
| # | Ward | KSI collisions | People KSI | Fatal | Main roads involved |
|---|---|---|---|---|---|
| 1 | Cathays | 17 | 19 | 2 | A4161 (5), A469 (2), A48 (1) |
| 2 | Penylan | 12 | 15 | — | A4161 (2), A4232 (2), A48 (1) |
| 3 | Plasnewydd | 12 | 12 | 1 | A469 (6), A4161 (2) |
| 4 | Riverside | 11 | 11 | 1 | B4267 (3), A4119 (2), A4161 (1) |
| 5 | Whitchurch and Tongwynlais | 10 | 14 | 1 | A470 (3), M4 (1), A4054 (1) |
| 6 | Butetown | 10 | 14 | 1 | A4160 (4), A4232 (3), A4234 (1) |
| 7 | Grangetown | 9 | 9 | — | A4232 (2), A4119 (1) |
| 8 | Caerau | 9 | 11 | 1 | A4232 (3), A48 (3) |
| 9 | Pentwyn | 8 | 8 | — | A48 (2) |
| 10 | Pentyrch and St Fagans | 8 | 12 | — | M4 (2), A4232 (1), A4119 (1) |
| 11 | Pontprennau and Old St Mellons | 7 | 12 | 1 | M4 (3), A48 (1), A4232 (1) |
| 12 | Heath | 7 | 7 | 2 | A469 (3), A48 (1) |
| 13 | Ely | 7 | 8 | 1 | A48 (3), A4232 (1) |
| 14 | Radyr | 6 | 6 | — | M4 (4), B4262 (2) |
| 15 | Rumney | 6 | 9 | — | A4232 (1), B4487 (1) |
| 16 | Gabalfa | 6 | 7 | — | A470 (2), A469 (1), A48 (1) |
| 17 | Canton | 5 | 5 | — | B4267 (1) |
| 18 | Trowbridge | 4 | 4 | — | — |
| 19 | Llanishen | 4 | 4 | — | B4562 (2) |
| 20 | Rhiwbina | 4 | 4 | 1 | M4 (3) |
| 21 | Llandaff | 3 | 3 | — | A48 (2), A4119 (1) |
| 22 | Fairwater | 3 | 3 | — | A48 (1) |
| 23 | Cyncoed | 3 | 3 | — | — |
| 24 | Splott | 3 | 3 | — | — |
| 25 | Adamsdown | 3 | 3 | — | A4160 (1) |
| 26 | Lisvane and Thornhill | 2 | 2 | — | M4 (2) |
| 27 | Llandaff North | 1 | 1 | — | A4054 (1) |
| 28 | Llanrumney | 1 | 1 | — | — |
Taking this to your ward councillor
These are the same records councils and road safety teams work from. Cite as “Analysis by Swift Assist (swiftassistuk.co.uk) of DfT STATS19 data, 2021–2025” with a link to this page. The CSV above carries every ward’s numbers for a briefing note.
Lines you can quote directly
- “210 people were killed or seriously injured on Cardiff's roads between 2021 and 2025, in 181 collisions recorded by police.
- “Half of those collisions happened in 9 of the city's 28 wards.
- “Cathays is the worst-affected ward, with 17 serious or fatal collisions and 19 people hurt.
- “The A48 accounts for 16 serious and fatal collisions across 10 wards, more than any other road in the city.
Need something more specific — a single junction’s history, pedestrian or cyclist casualties only, a printable one-pager for a ward meeting? Email the data desk. Ward-level requests from community groups are free.
Method: fatal and serious collisions (2021–2025) point-matched to ward polygons; casualty counts from the DfT casualty file. Collisions without valid coordinates excluded. Full methodology.
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