This elevated 10,000 square foot garden, located between Duke and Balderton Streets in Mayfair on the Grosvenor Estate, actually sits over the top of an electricity substation.

The now Grade II-listed substation was built in the early 20th century and the garden, which opened in 1906, was designed by Sir Charles Stanley Peach (also the designer of Wimbledon’s Centre Court) to provide some open space in what was then a working class residential area (not to mention its role disguising the substation below).

The garden replaced one which had formerly occupied the substation site and it was apparently at the insistence of the then-Duke of Westminster that the paved Italian-style garden be created following the demolition of the old garden.

It features a Portland stone domed gazebo and steps at either end.

The garden deck remained open until 1980 when it was closed by the London Electricity Board. It reopened in October, 2007. A refurbishment project several years later saw the addition of a glass-walled cafe at the western end and other improvements including new planter boxes, seats and a new water feature.

The surrounding housing blocks were built in the late 19th century to replace the poor housing that had previously existed and since 1973 have been under the care of the Peabody Trust.

WHERE: Brown Hart Gardens, Duke Street, Mayfair (nearest Tube stations are Bond Street and Marble Arch); WHEN: Daily, 8am to 8pm; COST: Free; WEBSITE: www.grosvenor.com/property/property-uk/brown-hart-gardens.