Shinetsu Five Mountains Trail Running Race 2025

Masatoshi Obara won the 2025 Shinetsu 100 mile in 19:52:07, and Tamami Arai won the women's race in 22:45:32 for 12th overall. The 110 km came down to 69 seconds: Ryoshin Hase held off Akito Nagao 12:20:26 to 12:21:35, and Naho Kotani won the women's race in 14:13:33.

It was a wet year, and the field spent it against the clock. The last 100-mile finisher came in at 32:57:46 with two minutes of the 33-hour limit to spare, and a fifth of the whole field finished inside the final half hour. The organiser recorded four runners past the limit rather than cutting them, at 33:01:24 and later, which is how a hard cutoff looks when it is honoured rather than a race that was stopped.

The 2025 course was not quite the 2026 one: snow damage had closed the Nishino power-station suspension bridge and forced a detour, and the race finished at Highland Hall Iizuna rather than the Plaza Aurora it moves to in 2026.