St Peter's Square is a public square in Manchester city centre, England. The north of the square is bounded by Princess Street and the south by Peter Street. To the west of the square is Manchester Central Library, Midland Hotel and Manchester Town Hall Extension. The square is home to the Manchester Cenotaph and the (currently closed for redevelopment) St Peter's Square Metrolink tram stop and incorporates the Peace Garden. In 1819, the area around the square was the site of the Peterloo Massacre.
The square is currently undergoing a controversial redevelopment project which includes the construction of a high rise office block, One St Peter's Square, to the south of the square. Two further high-rise office blocks are proposed opposite the Town Hall Extension (Two St Peter's Square) and on the former Odeon Cinema site.
The area around St Peter's Square, then known as St Peter's Field, was the site of the 1819 Peterloo Massacre. The name derives from St Peter's Church which was built in 1788-94 where the gardens are today and also gave its name to Peter Street. The church was built in the neoclassical style by the architect James Wyatt and was once famous for its church music. It was demolished in 1907 and the Cenotaph replaced it in 1924. A stone cross (1908) commemorates the church. The square is the site for the city's Remembrance Day commemoration each year.
In the 1930s, the square was redeveloped around the construction of the Central Library and Town Hall Extension (1930–34). Plans for a rapid transit station in St Peter's Square were made in the 1970s; proposals for the abandoned Picc-Vic tunnel envisaged the construction of an underground station to serve both St Peter's and the neighbouring Albert Square. The early proposals for an on-street light rail system in Manchester revived the idea of a station in the square, and the idea was retained as the project evolved, becoming a reality when the Metrolink system opened in 1992.