Hong Kong Four Trails Ultra Challenge (Chinese: 香港四徑超級挑戰), or HK4TUC (Chinese: 四徑; lit. 'Four Trails'), is an annual ultramarathon race in Hong Kong. Considered one of the most challenging mountain races worldwide, participants have to run through within 72 hours the famous quadruple hiking trails in Hong Kong known as "Four Trails": MacLehose, Wilson, Hong Kong, and Lantau. The ultramarathon spans a total distance of 298 kilometres with a cumulative elevation of 14,500 metres, starting from Tuen Mun and ends at the green post box outside Silvermine Bay Ferry Pier in Mui Wo.

The challenge was founded by Andre Blumberg, a German expat living in Hong Kong in 2012 when he decided to run the four trails in four days during the Chinese New Year holiday period.^[1] Blumberg later said he decided to challenge himself and get in shape as mid-life crisis loomed. Participation is strictly by invitation from Blumberg, who permitted around two dozens of runners every year. After an overhaul of the system in 2014, two titles of "finisher" and "survivor" are introduced. Runner could only earn the title of "finisher" if complete the four trails within 60 hours, and "survivor" in 72 hours.^[2] New rules were implemented to increase the difficulty, with hiking poles banned in 2021, painkillers in 2022, and watches in 2025.^[3]

The 2021 race only invited past finishers and survivors amidst the coronavirus pandemic. Prominent runners including Stone Tsang and Tom Robertshaw withdrew during the race, with Jacky Leung making history as the first that breaks the 50-hour mark.^[4] Four Trails, a film that documents that year's challenge, was released in 2025.

The challenge starts on the first day of the Lunar New Year, which usually falls in January or February. Spanning a total of 298 kilometres, the route has a cumulative elevation of 14,500 metres. Runners had to complete all the routes solo and self-supported with crew support allowed only off-trails. Sleep breaks and rests are allowed but will count into the timing.

The four trails, individually ran in reverse from the finishing point back to the start and in the following sequence, are:

• MacLehose Trail: 100 kilometres running west to east, from Tuen Mun New Town to Pak Tam Chung, traversing several country parks including Tai Lam, Tai Mo Shan (highest peak in the city), Shing Mun, Kam Shan, Lion Rock, Ma On Shan, and Sai Kung East and West
  • Runners must complete within the cut-off time of 18 hours
  • Runners will then be taken from the next starting point by car
• Wilson Trail: 78 kilometres running north to south, from Nam Chung to Stanley, traversing Pat Sin Leng, Tai Mo Shan and several hills in New Territories and Kowloon outskirt before crossing the harbour on the MTR underground, then passing through Quarry Bay and Tai Tam
  • Runners must cross the harbour on the MTR (Lam Tin station to Tai Koo station via Kwun Tong line, Tseung Kwan O line, and Island line)
  • Runners will then be taken from the next starting point by car
• Hong Kong Trail: 50 kilometres running east to west, from Tai Long Wan to Victoria Peak
  • Runners should take the ferry at Central Piers to the next starting point
  • Starting from 2023 runners can no longer travel by car and must reach the pier on foot^[5]
• Lantau Trail: 70 kilometres looping clockwise with starting and ending both at the green post box outside Silvermine Bay Ferry Pier in Mui Wo

The record holder is Wong Ho-chung who achieved a result of 46 hours 55 minutes in 2022. He, along with another local Jacky Leung, are the duo "breaking 50" achievement holders. Nikki Han and Cheung Man-yee are the two only female finisher.^[5] The youngest successful participant is Sarah Pemberton, completing the race in 70 hours 45 minutes in 2020 at the age of 26.^[6]

Only six runners claimed the "finisher" title twice: Nugo Yamanath Limbu, Jacky Leung, Salomon Wettstein, Hyun Chang Chung, Nikki Han, and Tomokazu Ihara.^[5]

	Finisher		Result	Year	Notes
1		Wong Ho-chung	46 hours 55 minutes	2022	Breaking 50
2		Jacky Leung Chun-keung	49 hours 26 minutes	2021	Breaking 50   Finisher Twice
			58 hours 31 minutes	2020
3		Salomon Wettstein	51 hours 53 minutes	2021	Finisher Twice
			54 hours 14 minutes	2018
4		Liu Fo-lok	52 hours 2 minutes	2024
5		Tom Robertshaw	53 hours	2017
6		Tomokazu Ihara	54 hours 2 minutes	2023	Finisher Twice
			57 hours 42 minutes	2019
7		Stone Tsang Siu-keung	54 hours 15 minutes	2017
8		Nugo Yamanath Limbu	54 hours 26 minutes	2020	Finisher Twice
			56 hours 29 minues	2023
9		Stephen Redfern	54 hours 46 minutes	2020
10		Kristian Joergensen	55 hours 52 minutes	2019
11		Thomas Lam Shing-yip	55 hours 32 minutes	2022
12		Eric Leung Wai-yip	56 hours 1 minutes	2024
13		Abimanyu Shunmugam	56 hours 6 minutes	2020
14		Ryo Doi	56 hours 25 minutes	2020
15		Joseph Yeung Chi-shing	56 hours 26 minutes	2022
16		Ryan Whelan	56 hours 54 minutes	2023
17		Wong Ka-kit	57 hours 11 minutes	2023
18		Richard Kimber	57 hours 27 minutes	2022
19		Jag Lanante	57 hours 45 minutes	2017
20		Cheung Man-yee	57 hours 53 minutes	2022
21		Phairat Varasin	57 hours 54 minutes	2018
22		Law Kai-pong	58 hours 11 minutes	2020
23		Tetsuya Fukui	58 hours 15 minutes	2024
24		Nikki Han	58 hours 20 minutes	2019	Finisher Twice
			59 hours 42 minutes	2021
25		Lau Chun-man	58 hours 55 minutes	2021
26		Leon Jiang Liangjun	58 hours 58 minutes	2024
27		Hyun Chang Chung	59 hours 23 minutes	2021	Finisher Twice
			59 hours 46 minutes	2020
28		Kevin Cheung Kei-fung	59 hours 30 minutes	2023
29		Mayank Vaid	59 hours 43 minutes	2024
30		Chiu Wen-hsiao	59 hours 45 minutes	2017
31		Law Chor-kin	59 hours 50 minutes	2021

• Hong Kong Marathon
• Trailwalker

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