The gardens, featuring a circuit of lime trees, were developed by William Montague to the specifications of the architect George Dance the Younger in 1815.

Fronting onto the circus from the 1820s was the substantial South Place Unitarian Chapel, erected under the leadership of William Johnson Fox; this evolved into Conway Hall Ethical Society.

[9] The gardens had previously been a private space for the use of the freeholders or lease-holders of the surrounding buildings, who objected to their compulsory purchase, fearing that their use by the public would create a nuisance which would lower the value of their property.

[12] Fronting the northwest quadrant of the oval, with fronts on roads entering the Circus from the west stands Edwin Lutyens's massive Britannic House (1921–25, listed Grade II), designed for the Anglo-Persian Oil Company, which became BP; its free-standing architectural sculptures are by Francis Derwent Wood.

In July 2020, the City of London Corporation announced the park would reopen to the public in August 2020, after a call in June for design proposals to transform the gardens into a sustainable multipurpose space.

[18] The winner of the design competition was announced in October 2020 as Architecture00 + Studio Weave, with Realm (previously called ReardonSmith Landscape), whose plan includes a one-storey garden pavilion constructed from natural materials.