Over the past 500 years, the urban development of apartment complexes, office buildings, and roads has swallowed up much of London’s green spaces. The Garden Museum, compiling photographs, paintings, and drawings, explores the secret history of London’s lost parks, pools, and gardens in a new show. Works on display include a photograph of Britain’s first urban ecological park, which existed on the banks of the Tower Bridge before closing in 1985, and a 1750 painting of the grassy courtyard behind Old Somerset House, as seen from the River Thames. Coinciding with a new book of the same name by Todd Longstaffe-Gowan, the exhibition argues for the preciousness of these fragile and increasingly rare urban parks. —Paulina Prosnitz