Prince of Wales Theatre seating capacity slightly to 1,160 seats and to modernise the theatre's facilities. New bars were added, the auditorium completely rebuilt, the backstage areas refurbished and the theatre's famous tower and exterior completely gutted and refurbished with new LED lighting and a crisp modern finish. The theatre re-opened with ABBA's musical "Mamma Mia!" on 16 April 2004. On 18 August 2007, "Mamma Mia!" became the longest-running show ever at the Prince of Wales, overtaking the previous record held by "Aspects of Love" with 1,326 performances at the venue and counting. The production marked another landmark on Thursday 23 August 2007, celebrating
HMS Prince of Wales (1902) two 3-cylinder vertical triple-expansion steam engines, each driving one propeller, which produced a total of , using steam provided by 20 Belleville boilers with economizers. The boilers had a working pressure of . She was the last British battleship built with Belleville boilers as they had proven problematic and uneconomical in earlier ships. The "London"s were designed to reach a speed of and "Prince of Wales" slightly exceeded this on her sea trials on 8 February 1908, reaching . She carried a maximum of of coal, enough to steam at a speed of . The "London"-class ships' main armament consisted