4 Trails Ultra Loop, aka 4TUL, was founded in 2020. The 189km loop starts and ends at Tai Mo Shan, 95% of the 4TUL route falls within the Hong Kong 4 major trails (namely MacLehose Trail, Wilson Trail, Hong Kong Trail, and Lantau Trail). The loop is connected by public transportation and to be done on foot with 146km.

The 1st edition of 4TUL was a 189km One Go challenge with almost 30 participants attempted the challenge.

4TUL started as a trail running race from the 2nd edition. Besides the 189km One Go challenge, there were also races from 1 section to 4 section in a row and team challenges.

The 3rd edition was slightly modified from the original course, yet the concepts of the course on the Hong Kong 4 major trails remains. It had been extended to 170km longest running distance with a total of 4 race categories, namely 100M Extreme, 100K Warrior, 50K Rocker, and 25K Speedster.

After 3 years of pandemic, the 4th edition of 4TUL in will be held as a physical race in 2024. The 4TUL loop remains, but the route direction will be reversed (anti-clockwise). The original 146km One Go route is back! 100km Warrior and 66km Half Loop are another two distances.

4 Trails Ultra Loop (簡稱4TUL) 始於2020年。路線為一個大環形，總距離為189公里，起點及終點均在大帽山。 95%的4TUL路線落在香港4條主要山徑 (即麥理浩徑、衛奕信徑、港島徑及鳳凰徑) 。完成這環形路線要以公共交通工具連接，實際需要跑步的距離約為146公里。​

第一屆4TUL 為一次性完成189公里個人挑戰，總參加人數約為30人。

第二屆4TUL 演變為的越野賽事， 除了189公里核心賽道，還增加一到四段分開完成及隊際接力的組別。

第三屆4TUL 在原本賽道上進行了輕微調整，但仍然保留以香港4條主徑作為比賽賽道的概念。賽事距離最長延伸到170公里 (跑步距離)，分為100M Extreme、100K Warrior、50K Rocker 及 25K Speedster 4個組別 。

經過3年的全球大流行，第四屆4TUL 終於可在2024年以實體賽事形式舉辦，意味參賽者可以享受一起在這大環形路線上作賽。賽事保留環形路線設計，但以反方向進行 (即逆時針方向)。原146公里路線在這屆會回歸！另外兩個距離分別為 100公里 Warrior 及 66公里 Half Loop。