Opened in 1898 at a cost of £3,000, Abertillery Workmen's Hall contained a library and reading room, committee rooms, and billiards room. Extended in 1901 to included a gymnasium, the building was enlarged again in 1908 at a cost of £1,600. A swimming baths was added in 1910. The original building was destroyed by fire and subsequently rebuilt in the 1950s. 

Daryl Leeworthy, RCAHMW, 12 September 2011.

In May 1909 the International Gymnastics Tournament was held at Powell's Tillery Gymnasium for the first time in history. The contests were between Wales, England and Scotland. The architects of the buildings were F. R. Bates of Newport (Institute, 1898), Mr Smith of Kidderminster (Institute new wing, 1908), and W. Beddoe Rees of Cardiff (swimming pool, 1910). For the new building constructed in the 1950s following the fire, a specially commissioned mosaic was placed above the main entrance onto Powell Street showing mining scenes with a centre piece of a phoenix rising from the ashes. Activities in the building ceased in 2016 and the building was put up for sale.

Meilyr Powel, RCAHMW, October 2020.

Source: 

'Powell's Tillery Miner's Institute - A History', outoftheblueartifacts.com