Edinburgh is a green city pricked with parks, but the jewel in the crown is the Botanic Gardens. Established in the 17th century as a Physic garden, today the 70-acre site is a haven of tranquility. Highlights include the Chinese Hillside, its slopes bushy with the largest collection of wild-origin plants outside China; the rock garden (5,000 plants at any one time); and the steamy Victorian Palm House. The state-of-the-art visitor center opened in 2009, its striking design a vertical vision of wood-cladding. The cutting-edge, low-carbon building houses a café upstairs that spills out onto the decking, and exhibition space, a shop, and a nursery. Inverleith House, an 18th-century mansion on the grounds, meanwhile showcases temporary art exhibitions. There are guided garden tours at 11am and 2pm during the summer, or just while away an hour or two beneath the magnificent trees, lying on the grass with a picnic.