A-road
A4048 traffic and collisions
The A4048 is an A-road of 11.8 miles, from Caerphilly to Blaenau Gwent. This page covers its traffic at 8 DfT count points since 2000 and the collisions police recorded on it.
- Traffic in 2025 38m vehicle miles
- Average daily traffic 8,827 vehicles a day, both directions
- Busiest section 20,794 A472 to A4048
- HGV share 2.2% of vehicle miles
- Traffic since 2019 +14.7% same count points
How busy is the A4048?
On an average day in 2025, 8,827 vehicles passed each point on the A4048, counting both directions. The busiest section is A472 to A4048 (Caerphilly), with 20,794 a day; the quietest listed is Rhiw Syr Dafydd Hill to B4511 Penylan Rd, with 5,683.
Busiest sections, 2025
A472 to A4048 carries 2.4 times the road’s average flow.
| Section | Vehicles a day |
|---|---|
| A472 to A4048 Caerphilly · 0.7 mi · HGVs 2.6% | 20,794 |
| At A4048 Caerphilly · 1.2 mi · HGVs 2.6% | 19,917 |
| A4047 Beaufort Road to A465 Heads of The Valleys Road Blaenau Gwent · 1.2 mi · HGVs 2.1% | 9,312 |
| At A4048 Caerphilly · 0.6 mi · HGVs 2.6% | 7,008 |
| B4511 Penylan Rd to road to Tredegar Caerphilly, Blaenau Gwent · 6.4 mi · HGVs 1.8% | 6,292 |
| Rhiw Syr Dafydd Hill to B4511 Penylan Rd Caerphilly · 1.4 mi · HGVs 2.3% | 5,683 |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Route
Caerphilly to Blaenau Gwent · 11.8 miles
A4048 traffic and collisions by section
7 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length.
Sections Tap a column heading to sort
| # | |||
|---|---|---|---|
| 1 | A472 to A4048Caerphilly | 20,794 | – |
| 2 | At A4048Caerphilly | 19,917 | – |
| 3 | At A4048Caerphilly | 7,008 | – |
| 4 | Rhiw Syr Dafydd Hill to B4511 Penylan RdCaerphilly | 5,683 | – |
| 5 | B4511 Penylan Rd to road to TredegarCaerphilly, Blaenau Gwent | 6,292 | – |
| 6 | road to Tredegar to A4047Blaenau Gwent | 6,984 | – |
| 7 | A4047 Beaufort Road to A465 Heads of The Valleys RoadBlaenau Gwent | 9,312 | – |
Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A4048 as the first road, placed on the nearest section by their recorded position; rates (per 100 million vehicle miles) are shown for sections of half a mile or more with 10 or more.
A4048 traffic by vehicle type
Cars and taxis make up 81.6% of the vehicle miles on the A4048. HGVs account for 2.2%.
Vehicle mix, 2025
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
HGV share of traffic
| Year | HGV share |
|---|---|
| 2000 | 2.5% |
| 2001 | 2.6% |
| 2002 | 2.6% |
| 2003 | 2.7% |
| 2004 | 2.7% |
| 2005 | 3.6% |
| 2006 | 3.6% |
| 2007 | 5.0% |
| 2008 | 3.9% |
| 2009 | 3.4% |
| 2010 | 3.6% |
| 2011 | 3.6% |
| 2012 | 3.8% |
| 2013 | 3.7% |
| 2014 | 3.6% |
| 2015 | 3.4% |
| 2016 | 3.3% |
| 2017 | 3.0% |
| 2018 | 3.0% |
| 2019 | 3.0% |
| 2020 | 3.6% |
| 2021 | 3.5% |
| 2022 | 3.3% |
| 2023 | 3.1% |
| 2024 | 2.2% |
| 2025 | 2.2% |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
A4048 traffic trend
Traffic on the A4048 came to 38 million vehicle miles in 2025. At the count points present in both years, it is up 14.7% on 2019, before the pandemic, and up 17.1% on 2015.
Vehicle miles a year
Like for like, traffic is up 29.4% on 2000.
| Year | Vehicle miles |
|---|---|
| 2000 | 43m |
| 2001 | 42m |
| 2002 | 43m |
| 2003 | 42m |
| 2004 | 43m |
| 2005 | 44m |
| 2006 | 44m |
| 2007 | 29m |
| 2008 | 30m |
| 2009 | 31m |
| 2010 | 31m |
| 2011 | 31m |
| 2012 | 31m |
| 2013 | 30m |
| 2014 | 31m |
| 2015 | 32m |
| 2016 | 33m |
| 2017 | 33m |
| 2018 | 33m |
| 2019 | 33m |
| 2020 | 25m |
| 2021 | 27m |
| 2022 | 30m |
| 2023 | 31m |
| 2024 | 37m |
| 2025 | 38m |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Average daily flow
| Year | Vehicles a day |
|---|---|
| 2000 | 7,453 |
| 2001 | 7,346 |
| 2002 | 7,455 |
| 2003 | 7,354 |
| 2004 | 7,476 |
| 2005 | 7,646 |
| 2006 | 7,645 |
| 2007 | 6,854 |
| 2008 | 7,240 |
| 2009 | 7,402 |
| 2010 | 7,435 |
| 2011 | 7,439 |
| 2012 | 7,329 |
| 2013 | 7,260 |
| 2014 | 7,449 |
| 2015 | 7,729 |
| 2016 | 7,928 |
| 2017 | 7,863 |
| 2018 | 7,798 |
| 2019 | 7,815 |
| 2020 | 5,917 |
| 2021 | 6,521 |
| 2022 | 7,032 |
| 2023 | 7,355 |
| 2024 | 8,714 |
| 2025 | 8,827 |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
The chart counts the whole road as it was each year, so new or renumbered stretches move it. The percentage changes compare only count points present in both years (89.8% of today’s road for 2019). In 2025, 0 of the 8 count points were counted; DfT estimated the rest from earlier counts and local trends.
A4048 collisions
Police recorded fewer than 3 collisions with the A4048 as the first road from 2021 to 2025, 11 of them fatal or serious.
Reported collisions by year
| Year | Collisions | Fatal or serious |
|---|---|---|
| 2021 | 6 | 4 |
| 2022 | 8 | 3 |
| 2023 | 4 | fewer than 3 |
| 2024 | 5 | fewer than 3 |
| 2025 | fewer than 3 | 0 |
Source:DfT STATS19,UK Motoring analysis 2021 to 2025 Updated
A further 3 collisions were recorded at junctions where the A4048 was the second road; they are not in the figures above. Fatal or serious uses DfT’s adjusted serious figures. How we count collisions
Council areas on the A4048
In route order. Each is the highway authority DfT files the count points under.
- Caerphilly
- Blaenau Gwent
Data sources and methodology
| Figures | Source | Period | Records | Updated |
|---|---|---|---|---|
| Traffic counts and vehicle mix | Road traffic statistics (AADF by count point) Department for Transport Derived statistics UK Motoring | 2000 to 2025 | 8 count points in 2025 | 15 September 2026 |
| Reported collisions | Road safety open data (STATS19) Department for Transport Derived statistics UK Motoring | 2021 to 2025 | 25 reported collisions | 15 September 2026 |
- Annual average daily flow (AADF) is the average number of vehicles passing a point on a typical day of the year, both directions combined.
- Vehicle miles are AADF multiplied by link length and 365, summed over every count point link on the road.
- Sections join count point links between junctions, using the link lines in DfT’s major road database.
- STATS19 covers personal injury collisions reported to the police. Damage-only collisions are not included, and not every injury collision is reported.
- Serious and slight figures are DfT’s adjusted estimates, which allow for police forces moving to injury-based reporting.
- Counts of one or two collisions below Great Britain level are shown as “fewer than 3”.
Contains public sector information licensed under the Open Government Licence v3.0.