ハセツネ – Hasetsune , the Most Famous Trail Race in Japan

Perhaps the most famous trail race in Japan is Hasetusne. It takes place every October in the mountains of western Tokyo. A 71.5K loop, starting and finishing in the town of 武蔵五日市 – Musashi Itsukaichi in あきる野市 – the Akiruno district. The endurance element of the race – there is only one spot during the race where fluid replenishment (water or sports drink) is provided – turns many casual trail runners away.

Even so, the race is quite difficult to get into. The organizers do not employ a lottery system. There are two ways the common trail runner can gain entry:
1. Finish in the top 500 men / 250 women in the previous spring’s Hasetsune 30K
2. Try your luck online at 10am on June 1.

Check out our detailed course description, starting with Hasetsune Course: Start to Mt Imakuma.

The History

There was an effort by the Tokyo Metropolitan Mountain Federation in 1993 to put on an event to encourage more participation in mountain adventure activities. The October date coincided with both the National Sports Day holiday and the anniversary of the recent passing of the legendary Japanese alpinist and TMF member Hasegawa Tsuneo. The race continues in his memory – the name Hasetsune is an abbreviation of his name, the first two syllables from his first and last name – Hase Tsune.

Hasegawa was a native of Kanagawa Prefecture. He grew up in the foothills of the Tanzawa mountains, and started climbing at the age of 15. He cut his teeth on the ranges in Japan in all four seasons. At 23 became an official guide in the Japan Alpine Guide Association. He climbed around the world, and notably was the first to accomplish some significant winter solo efforts – the North Face Trilogy in Europe (Matterhorn, Eiger, Grandes Jorasses), and the South Face of Aconcagua in Argentina. He died in an avalanche on the southeast face of Ultar II on October 10, 1991. His remains were buried in Pakistan. 20 years after his death, on October 10, 2011, a stone monument to Hasegawa was unveiled on the trail where the Hasetsune course intersects the ancient Mitake Shrine.

The original intention of the race was to promote adventure in nature. Over time, heavy backpacks and climbing boots gave way to the ultralight hydration vests and tail shoes. Interestingly, the alpinist Hasegawa has become the focus for many a trail runner.

The race is now organized by the Japan Mountain Sports Association.

The Athlete Demographic

The race is primarily run by Japanese trail runners (no wonder – it takes place in Japan). It is seen as a coming of age race for many Japanese racers, including Ishikawa Hiroaki, Kaburagi Tsuyoshi, Okunomiya Shunske, and Ueda Ruy (Ueda was born only a week before the inaugural Hasetsune was run).

The entrants are primarily male, averaging around 85% for the pre/post pandemic period. The age group splits are roughly the same for men and women, with the 40 year old bucket at around 45%, followed by 50s at just under 30%.

A few notable foreign elites have participated:

Scott Jurek: 18th in 2003
Brandon Sibrowsky: 19th in 2003 (one second ‘behind’ Scott Jurek)
Chrissy Moehl: 3rd in 2003
Ludovic Pommeret: won in 2010
Dakota Jones: set a then course record in 2012 of 7:22:07 (race report: https://www.irunfar.com/hasetsune-mr-jones-goes-to-japan-and-wins)
Amy Sproston: won in 2014
Max King: 8th in 2014

Cancellations

From the off, the timing in October meant that autumn rains were in play. Course markings were set the days before the first race in a typhoon, though the race day turned out to be perfect.

That said, the race has only been cancelled once due to the effects of a typhoon – In 2019

In 2020 and 2021 it was canceled due to concerns around the coronavirus pandemic.

The Course

Screen Shot 2022-10-16 at 9.29.13 PM A few area routes were considered for the first race, including the 30k North/South Takao Ridge loop, and trails in the Okutama/Ishione area. The final route was chosen, in part, due to the few and relatively safe road crossings.

Originally there were two distances, the half and the full. The half distance race only lasted for one year. In 2009, the inaugural Hasestune 30K was run. The 30K is conducted on day in the early spring.

Later, in 2022, the organizers again introduced a second distance category, the double. The double had the same 24 hour cutoff as the original Hasetsune Cup, and is a consecutive pair of loops in the clockwise direction.

In the first iteration of the race, the direction of the course for the full and the half was opposite of today’s version.

The full course on yamap: https://yamap.com/activities/2927888
The original half: https://ibuki.run/c/8961576220845062063/#map

Check out our guide to reading the permanent course markings, and a detailed breakdown of the entire course in the links at the bottom of the page.