The New Territories is the largest part of Hong Kong — the mainland peninsula north of Kowloon and a number of nearby islands, leased by Britain from China in 1898 for 99 years. The 1997 handover was driven largely by the expiry of this lease, since the colony couldn't survive without the New Territories' land and water supply.
Despite rapid urbanisation in the south, the New Territories still offers a genuine contrast to the density of Kowloon and Hong Kong Island. Walled villages built in the 16th and 17th centuries survive in the west — Kam Tin (Kat Hing Wai) is the most visited, though somewhat touristified. The Tsang Tai Uk walled village in Sha Tin is larger and better preserved: a 19th-century granite compound built for a quarry master's clan, still partially inhabited.
The Sai Kung peninsula in the east is the wildest and most scenic part of the territory. Country parks cover most of it, with excellent hiking trails and, on the outer peninsula, some of the best coastline in Hong Kong. Ferries from Sai Kung village take you to uninhabited islands with clear water and empty beaches. Sai Kung town itself has a harbour lined with floating seafood restaurants.
Sha Tin is home to the Hong Kong Heritage Museum (good permanent collection on Cantonese opera and Bruce Lee, among other subjects) and the Sha Tin Racecourse, one of the world's largest, which can hold 85,000 spectators and hosts meetings on Saturdays and Sundays from September to June.
The east-west MacLehose Trail (100km) and the north-south Wilson Trail are the main long-distance hiking routes through the New Territories; both are well-maintained and properly signposted.