Mount Fuji saw 2.5 percent fewer climbers this summer than the year before because tighter restrictions on vehicle use defied expectations for a sharp increase in visitors tied to its listing as a UNESCO World Heritage site.

The tally of 310,721 climbers, released Tuesday by the Environment Ministry and covering the July 1 to Aug. 31 climbing season, was compiled via infrared counters near the mountain's 8th stations on each of the four climbing trails. The data differ from figures by local municipalities, which count visitors near the 5th and 6th stations.

The nation's highest peak set its record of 320,975 climbers in 2010. The ministry began keeping records in 2005.

Earlier this year, the ministry extended a ban on private cars from roads leading to the entry points for three of the peak's four trails, resulting in fewer visitors. The ministry also said the decline stemmed from calls to refrain from ascending to the 3,776-meter summit without sleep or rest, which can cause altitude sickness. Some also steered clear of the mountain this year in anticipation of congestion from the World Heritage hoopla.

The Yoshida trail on the Yamanashi Prefecture side was the most popular of the four routes, attracting 179,720 climbers but still down 5.3 percent from the previous summer. Among the three routes that start in Shizuoka Prefecture, the Fujinomiya trail was taken by 76,784 climbers, the Subashiri trail by 36,508 and the Gotemba trail by 17,709, the ministry said.