Piccadilly Circus was originally formed in 1819 by the intersection of Piccadilly and Nash's New Street. It was one of the two links which joined together the three sections of Regent Street, and was known as Regent Circus South, Oxford Circus being called Regent Circus North. Northwards from the Circus a short length of street, terminated at the north end by the County Fire Office, led to the Quadrant on the west and to an opening into Tichborne Street on the east. The original buildings in the Circus will be described and illustrated in a later volume of the Survey of London which will be concerned with the whole of Regent Street. Since the formation of Shaftesbury Avenue in the 1880's, however, Piccadilly Circus has ceased to be a circus, and has become the most famous place in the whole of London. It cannot be considered in isolation from either Shaftesbury Avenue or the Regent Street Quadrant, and its evolution away from Nash's original plan therefore comes within the scope of the present volume.

The construction of the south end of Shaftesbury Avenue involved the removal of the triangular block of buildings which formed the south-west side of Tichborne Street. This triangle also formed one of the segments of Nash's Piccadilly Circus, and its removal reduced the Circus to an undistinguished and ill-shaped vortex of converging streets.

Shaftesbury Avenue was opened in January 1886.

Text extracted from British History Online, a digital library of key printed primary and secondary sources for the history of Britain and Ireland, with a primary focus on the period between 1300 and 1800.
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