St Asaph (/sənt ˈæsəf/; Welsh:Llanelwy [ɬanˈɛlʊɨ̯]) is a city and community on the River Elwy in Denbighshire, Wales. In the 2011 Census it had a population of 3,355 making it the second-smallest city in Britain.

The city of St Asaph is surrounded by countryside and views of the Vale of Clwyd. It is situated close to a number of busy coastal towns such as Rhyl, Prestatyn, Abergele, Colwyn Bay and Llandudno. The historic castles of Denbigh and Rhuddlan are also nearby.