Chelsea Physic Garden

Founded in 1673, Chelsea Physic Garden contains the world's oldest rock garden, made from fused bricks and flint, stones from the Tower of London, and Icelandic lava brought up the Thames by ship in 1772. Today the garden is also home to Britain's first garden of ethnobotany (the study of the botany of different ethnic groups and indigenous peoples). The garden is open Tuesday, Wednesday, Thursday, Friday, Sunday and bank-holiday Monday afternoons from April to October. There's a shop where visitors can buy unusual plants and a café that serves very good homemade cakes.