This research established the impact of recent major road transport infrastructure improvements on economic development in Wales with the aim of informing the appraisal of future projects.
Mae'r ymchwil wedi sefydlu effaith gwelliannau seilwaith mawr cludiant ar y ffordd ar ddatblygiad economaidd yng Nghymru gyda'r nod o lywio'r broses o arfarnu prosiectau yn y dyfodol.