Surely the UK's crowning garden jewel, Kew Gardens is a UNESCO World Heritage Site boasting 37 acres of woodland, 14,000 trees and over 50,000 living plants. Kew Palace is where its rich history, spanning nearly 400 years, began; the Arboretum is a living library of trees; and the Marianne North Gallery boasts over 800 paintings of plants and flowers.
There are also several beautiful historic follies scattered throughout the gardens, including the Pagoda, built in 1762 for Princess Augusta.