Glynneath is home to the ruins of
Aberpergwm House. Once owned by Rhys ap Siancyn, Aberpergwm House became the home of the Williams family, Welsh gentry with a strong tradition of using the Welsh language over English. Their descendants include the last of the Welsh household bards
Dafydd Nicolas and folksong collector
Maria Jane Williams. The Williams' family motto
y ddioddefws y orfu (He who suffers, triumphs) was adopted by
Glamorgan County Council. The mansion itself was remodelled in 1876 but is now derelict and little of note remains of the building.
St. Cadoc's Church, in the grounds of Aberpergwm House, was built as a chapel in the 17th century, rebuilt in 1808-1809 for the Aberpergwm Williams family and extended in 1836–41. It is a Grade II* listed building.
Rheola House, a Regency house designed c.1812 by the eminent architect
John Nash, is also Grade II* listed. Glynneath Town Hall is a regularly used civic building situated at Heathfield Avenue. It is owned and managed by Glynneath Town Council. The Grade II* listed Bethania Community Centre on the High Street is an example of an early Calvinistic Methodist chapel with well detailed external frontage in contrasting stone and iron work railings. The interior has good examples of very finely detailed woodwork. A bronze statue of the singer
Max Boyce, who was born in the town, was erected in the High Street, in September 2023, in recognition of Boyce's 80th birthday. == Sports and leisure ==