It is best known now as the "second hand book capital of the world", as a vast number of such bookshops have opened since the 1960s, followed by antique and craft shops.
Hay-on-Wye Castle dates from the Norman period, but was largely destroyed by King John. The site comprises ruins attached to an Elizabethan mansion, which itself now houses a bookshop.
There is a covered Butter Market dating from the mid 19th century.
The prestigious Hay Literary Festival takes place in early Summer.