Ceredigion may be Greg Stevenson's home county, but the architectural historian admits that finding very old houses in this part of West Wales is a rarity.

Greg, along with presenter Aled Samuel, however did discover one real gem of a house dating back to the 15th century.

Sir Aberteifi or Cardiganshire – now known as Ceredigion – is the first county in their 13 programme long exploration. An amazing Victorian home in Aberystwyth, an ancient farmhouse near Strata Florida and a tin-roof cottage near Llanarth, are featured in this programme. But Plas y Wern, a small mansion near New Quay, with its oldest wing dating from the 15th century, is arguably the piece de resistance.

Greg Stevenson explains, “Some areas of Wales are filled with houses from the 15th century onwards, but not in Cardiganshire. Aside from the castles and some churches, there aren't a lot of old buildings in the county. But here, there's an old house from the 15th century with an extension from the 1670s. The two parts don't sit comfortably together – and that's great to see, because it's a house that says a lot about two different eras.”

In the Georgian part of the house, some of the walls are covered by wood panelling, made from pine imported from Scandinavia, as early as 1670. At the top of the house is an incredible hall-like room. In the 1930s when Alastair Graham, friend of the author Evelyn Waugh, owned the house, this unlikely upstairs room saw its share of raucous parties.