One of the easiest trails starts at the northern end of the village and leads up Monbestu-dake (紋別岳; 866m), which takes around one hour and twenty minutes to climb. The hike up Eniwa-dake (恵庭岳; 1319m), on the north side of the lake above the Poropinai campsite, is more challenging and takes at least two and a half hours; staff at the visitors’ centre advise only climbing to the Miharashi-dai, beneath the 1319.7m summit, because the trail to the top can be dangerous. After this climb, you could unwind beside the lake at the foot of the mountain in the lovely rotemburo at Marukoma Onsen.
Most people, however, opt to climb Tarumae-zan (樽前山), an active volcano (the last eruption was in 1951) south of the lake. The hike begins at the seventh “station”, three-quarters of the way up the volcano at the end of a dirt road; the easiest way of reaching the start is to hitch a ride from Shikotsu-ko. The walk from the seventh station up to the summit (1041m) shouldn’t take more than an hour. At the top, the pungent aroma from the steaming crater discourages lingering. Following the northwest trail down from Tarumae-zan towards the lake leads, after a couple of hours, to the moss-covered gorge of Koke-no-dōmon (苔の洞門); sadly, erosion at this site means that you’ll only be able to view the soft green velvet rock walls from a distance. From here it’s a 14km hike back to Shikotsu-ko Onsen.