Event Detail
The Lake Saroma 100km Ultra Marathon is scheduled for Sunday 27 June 2027 on the shores of Lake Saroma in eastern Hokkaido, Japan. The date is listed by the Association of International Marathons and Distance Races (AIMS), of which this long-established road ultramarathon is a full member. The organiser's own website still displays the completed 2026 edition, so the 2027 entry timetable, start arrangements, confirmed race programme and fees should be treated as not yet announced.
Why this race matters
Lake Saroma is one of Japan's best-known road ultramarathons. A preparatory event took place in 1986, followed by the first official race in 1987. Its history includes an international IAU World Challenge meeting in 1994, an IAU World Cup in 2005 and several landmark 100 km performances. The organiser documents world-best runs by Takahiro Sunada in 1998 and Tomoe Abe in 2000, while Nao Kazami set another world-best time in 2018. This depth of competitive history makes the event a significant date for experienced ultrarunners and followers of Japanese endurance sport.
Course and location
The traditional route is a 100 km road race through the Lake Saroma region, connecting communities around the Okhotsk coast. The 2026 course started outside Yubetsu General Gymnasium and finished at the Tokoro Sports Centre in Kitami. That edition used a course certified by AIMS and the Japan Association of Athletics Federations. Lake Saroma's shoreline, open landscapes and long stretches of tarmac provide a distinctive setting, but competitors should prepare for the distance, possible coastal winds and changing conditions rather than assuming that a relatively flat road profile will make 100 km easy.
The 2026 edition also included a 50 km option starting at Saroma Town's 100 Years Square. It used 05:00 and 10:00 local starts for the 100 km and 50 km respectively, with 13-hour and eight-hour finish limits. These are previous-edition details only, offered as background for prospective entrants; they must not be assumed to apply in 2027. The 2027 100 km date has been confirmed by AIMS, but the organiser has not yet published a detailed current-edition guide.
Planning for 2027
Check the official Japanese race website and its linked RUNNET entry pages for the opening date, quotas, age requirements, travel and baggage-transfer arrangements once the 2027 regulations are released. Transport between the traditional start and finish areas matters because the course is point to point and spans several municipalities. Accommodation in the Okhotsk region may require early planning. Do not rely on 2026 prices or registration deadlines when making arrangements for June 2027.
Latest verified information: race date 27 June 2027 (AIMS); race-day start time, bib collection, entry prices, 2027 start venue and any 50 km event await current-edition confirmation.