Newcastle Emlyn is 10 miles south east of Cardigan and 8 miles west of Llandysul on the A484 in both Carmarthenshire and Ceredigion, West Wales. Unusually the town can be said to be in two counties as the northern district of Newcastle Emlyn, Adpar, sits on the north bank of the Teifi in the county of Ceredigion, while Newcastle Emlyn district sits on the south bank of the Teifi in Carmarthenshire.

The two parts Newcastle Emlyn and Adpar together form a bustling market town which grew up around a crossing point over the River Teifi, its swooping meanders made the site a natural defensive position. Today, although the castle is in ruins, the town is lively and attractive and its people welcoming.

The castle was probably founded by Maredudd ap Rhys around 1240, and if this is so, it is one of the few castles in Dyfed built by the Welsh in stone. The time-worn remains sit on a picturesque, grassy site overlooking a loop on the River Teifi, and were once inhabited by Sir Rhys ap Thomas, friend of Henry VII. It would be hard to imagine a more serene setting than this, and one is not surprised to find that it was once intended as a county seat rather than a military post. Yet it had its share of excitement in the Civil War, when held for the king and blown up with gunpowder at the close of the struggle. Today all that remain are remnants of some of the walls and the ruins of the gate.

Elsewhere in Newcastle Emlyn you can find a leisure centre, swimming pool and several public houses and independent shops. Both Cenarth and Henllan Falls can be found nearby, with beautiful scenery and magnificent views of the waterfalls. The Museum of Childhood, one mile north of Llangeler, commemorates 100 years of childhood experiences in Ceredigion and the surrounding counties, and provides a fascinating and fun day out for everyone. The Emlyn Arms Hotel provides a comfortable night's stay in the town, whilst many self-catering cottages surround the town.