A465 road

In 1990, a regional traffic study identified the need for improvements to the A465. In 1994, alternatives were presented for public consultation for the improvement of the 25-mile length between Abergavenny and Hirwaun, connecting the existing A465 dual carriageway link from Swansea to the A40, which is an important part of the route to the M50. In July 1995 the then Secretary of State for Wales announced the preferred route. This mainly consisted of widening the existing road to provide a dual carriageway standard with grade-separated junctions (and extra climbing lanes on certain hills) between Abergavenny and Hirwaun. The design was developed and a draft line order was published in 1997. This was tested at public local inquiry in 1998 after which the Secretary of State for Wales announced the decision to proceed with the scheme in 1999.

Much of the land on the route is undulating, but despite this, the preferred route alignment is considered to be of high standard and as such allows most of the route to have the national speed limit.[7]

Initially, the upgrade was split into seven sections. Later, sections 6 and 7 were combined into a single scheme for the purposes of construction.

The section between Llandarcy and Hirwaun is already dual carriageway. Construction works began on section 4 (Tredegar to Dowlais Top) in early spring 2002, and were completed by November 2004. Construction of section 1 (Abergavenny to Gilwern) began in February 2005. This section is a largely on-line upgrade of the existing single-carriageway road. This section was completed on 22 May 2008.

The contract for Section 3 – Brynmawr to Tredegar was awarded to Carillion in March 2010 with planning commencing soon after, it was announced in August 2012 that approval for the scheme to commence had been given and that construction should commence by the end of 2012 with completion due by early 2015.[11]

Planning for Section 2 – Gilwern to Brynmawr started in June 2011 and construction began in January 2015 and was expected to last until 2017.[12]. Construction is continuing in 2020.[13]

The National Transport Plan, published in March 2010, expected Brynmawr to Tredegar to be completed by 2014 and Gilwern to Brynmawr started by the same date. The remaining sections from Dowlais Top to the A470, and from the A470 to Hirwaun were to be completed by 2020.[14] Speaking in the Senedd in August 2010, the First Minister said completion of the A465 upgrade was the ultimate solution to the high number of casualties on the road.[15]

As of December 2019, construction of sections 5 and 6 has not begun and the business case for the project will be reviewed before a final decision is made.[16]