Mount Pleasant Mail Centre was built on the location of the former Coldbath Fields Prison whose prison gate was incorporated into the building while the rest was demolished in 1929
It was built on the location of the former Coldbath Fields Prison that ceased to function in 1885. The original prison gate was incorporated into the Post Office building and not demolished until 1901. The remaining sections of the prison were demolished in 1929, when the new wing was built as an extension to the Letter Office. 
