The starting point of Section 4 of the Hong Kong Trail is located on Aberdeen Reservoir Road near Wan Chai Gap. Follow the "Hong Kong Trail" waymark into a shaded path, reaching the junction of trails towards Wan Chai Gap and Black's Link. Continue towards Black's Link, and soon you will arrive at a stone bridge. From there, walk to the Locality Pillbox 13. In the late 1930s, the British garrison set up defence positions in the valleys and built over a hundred "Type A" shelters and locality pillboxes on Hong Kong Island. The Aberdeen Reservoirs Defence Position had a few locality pillboxes and "Type A" shelters. Locality Pillboxes 13 has four embrasures. Each is two-feet wide, with a 100° firing arc and was protected by iron gates. The embrasure was operated with Vickers machine gun to resist attacks from the west and south. When visiting, please respect the historic relics and refrain from entering or damaging them. After the visit, continue to the junction of trails towards Black's Link and Aberdeen Upper Reservoir. Proceed towards Black's Link, passing a catchwater and shaded path, then walk approximately 700 m uphill. This section requires some physical effort, so please be mindful of sun protection and hydration. After completing the uphill section, continue to the Middle Gap Viewing Point, where the view is expansive, offering a distant view of Ocean Park and Brick Hill. After that, walk along a shaded path to reach the junction of trails towards Wan Chai Gap and Wong Nai Chung Gap Road. Proceed towards Wong Nai Chung Gap Road until reaching the Tai Tam Reservoir Road Sitting-out Area, which marks the end of Section 4 of the Hong Kong Trail.

Due to landslide caused by heavy rain, part of Black’s Link along Hong Kong Trail Section 4 (see attachment) is temporarily closed for maintenance and clearance from 12 July 2025 until further notice. We apologise for any inconvenience caused.

_{To facilitate the public in planning their hikes, the geographical information of the route, including the route map, starting point, endpoint, and elevation chart, has been saved in a "GPX" file. The public can download hiking-related applications on their smartphones or smart watches, then click on the following "GPX" file to import the relevant information, which serves as an aid for hiking. Please note that downloading "GPX" files may increase data usage, and the functions and content display may vary depending on the device and application used.}