Ranelagh Pleasure Gardens in London’s Chelsea opened in 1742 on the site of Ranelagh House, a house built by the First Earl of Ranelagh in 1688-1689 on land adjacent to Chelsea Hospital, on the north bank of the Thames. With an ornamental lake and Chinese pavilion, Ranelagh Gardens soon became more fashionable that the neighbouring Vauxhall Gardens. Ranelagh became well known for fashionable masquerades, and also established itself as a venue for concerts in the open air in the dramatic central wooden Rotunda, built by William Jones and modelled on the church of St. Sophia in Constantinople. In 1751 the artist Canaletto (1697-1768) painted views of the Rotunda and the gardens commissioned by the printseller Robert Sayer (1725-1794), and on 29 June 1764 the nine year old Mozart performed a concert there on harpsichord and organ. The heated hall of the Rotunda with its supper boxes gave Ranelagh an early advantage over Vauxhall, which had no indoor concert venue until the late 1740s, when Jonathan Tyersinstalled an assembly room and concert hall in time for the opening of the 1748 season, inspired by Ranelagh's Rotunda, but half its size.

Chamberlain’s History of London, 1770, described Ranelagh as: ‘one of those public places of pleasure which is not to be equalled in Europe’ and described the Rotunda as a circular building with an external diameter of one hundred and eighty-five feet...: ‘round the whole is an arcade, and over that a gallery with a balustrade (to admit the company into the upper boxes) except where windows break the continuity. Over this are the windows, and it terminates with the roof. The internal diameter is one hundred and fifty feet, and the architecture of the inside corresponds with the outside, except that over every column, between the windows, termini support the roof. In the middle of the area, where the orchestra was at first designed, is a chimney having four faces. This makes it comfortable in bad weather. The orchestra fills up the place of one of the entrances. The entertainment consists of a fine band of music, with an organ, accompanied by the best voices. The regale is tea and coffee.’