About This Race
The 104-kilometer distance at TransJeju by UTMB represents the marquee ultra-distance event in this UTMB World Series qualifier, traversing Jeju Island's volcanic landscape from coast to interior. The course showcases the full ecological spectrum of this UNESCO World Heritage site, from subtropical coastal zones through temperate forests to the alpine environments near Hallasan, South Korea's highest peak. As part of the UTMB World Series, this distance offers qualification points for runners targeting UTMB Mont-Blanc and other marquee events in the circuit. The extended nature of this ultra demands comprehensive preparation beyond basic fitness. Runners will spend considerable time navigating the island's volcanic rock formations and experience dramatic shifts in both temperature and vegetation zones as they gain and lose elevation. The technical terrain requires confident footing on basalt rock, while the distance itself calls for dialed-in fueling strategies and mental fortitude through the inevitable low points that come with any 100K effort. Jeju Island's October conditions typically provide favorable running weather, though the maritime climate means conditions can shift quickly. The island's established trail running infrastructure and UTMB's production standards ensure well-marked courses and regular aid stations, but this remains a serious undertaking requiring respect for the distance and terrain.
The 104K course moves through Jeju Island's diverse volcanic terrain, with runners experiencing the full range of ecosystems that make this UNESCO site distinctive. The route incorporates technical sections across basalt formations, the island's characteristic volcanic rock that requires careful foot placement and sustained concentration. Vegetation transitions from coastal subtropical forests through temperate zones, with temperature and exposure varying significantly depending on elevation and proximity to Hallasan.
Location
Practical Info
October on Jeju typically brings moderate temperatures with daytime highs around 20°C (68°F), though maritime conditions mean weather can shift quickly. The island's position in the Korea Strait creates variable conditions, and runners should prepare for potential rain and wind, particularly at higher elevations.
CJU - Jeju International Airport
Jeju City offers extensive lodging options ranging from international hotels to local guesthouses, with good English-language support in tourist areas. The island is well-developed for tourism with reliable public transportation, though many runners opt to rent cars for flexibility in accessing the race start and exploring the island before or after the event.
Best For
Notable Features
Part of the UTMB World Series, offering runners both qualification points and the opportunity to experience South Korea's only UNESCO World Heritage natural site. The course showcases Jeju Island's unique volcanic geology, formed by eruptions over millions of years, with technical sections across basalt rock formations. The island's position in the Korea Strait creates a distinctive maritime climate and ecological diversity rare for its latitude, with subtropical and temperate ecosystems converging in a compact area.