One of the most recent high-rise buildings to be constructed and opened within the city centre itself is Ian Simpson's Holloway Circus Tower, which opened in January 2006. When topped out, it became the second tallest building in Birmingham at , only being beaten by the BT Tower. This has been prompted by the publication of the city council's ""High Places"" document which outlined locations along the city centre sandstone ridge that were deemed appropriate for the construction of high rise structures.