Two routes were suggested for the British Section, a western route of about from the tip of Kowloon peninsula via Tsuen Wan to Castle Peak Bay and thence to Yuen Long and the border with China, and a more direct eastern route of about requiring tunnelling through the Kowloon hills and thence to the border via Tide Cove (Sha Tin), Tai Po, Fanling and Sheung Shui. Following a detailed survey in 1905, the eastern route was proposed. Although the formal approval of the Colonial Office in London was not given until February 1906, the Governor, Sir Matthew Nathan, had anticipated a positive outcome and had already instructed the Public Works Department to start earthworks on the route from Tai Po Market to Fanling in December 1905.