Mount Idonnappu

イドンナップ岳

Shinhidaka, Hokkaido · Elevation 1,752 m

Mount Idonnappu is a 1,752 m peak on the boundary of Niikappu and Shinhidaka towns in Hokkaido, standing on a side ridge extending west from Mount Harube in the western Hidaka Range. The name derives from the Idonnappu River that drains its slopes, with one Ainu etymology meaning 'ant'. The route from Niikappu Lake covers roughly 20 km with 1,800 m of cumulative gain through sasa bamboo bushwhacking and steep climbs, earning it a reputation as one of the toughest single-day climbs in Hidaka. The mountain lies within the Hidaka-Sanmyaku-Erimo-Tokachi National Park designated in 2024 and is counted among the 100 Famous Mountains of Hokkaido.

Mount Idonnappu at a glance

Weather: The most settled day in the next 7 days is Mon, November 9: cloudy, gusts up to 12 m/s. Wed, Nov 4, Fri, Nov 6, Sat, Nov 7, Sun, Nov 8: strong wind (gusts up to 25 m/s).

Mount Idonnappu weather (hourly, 14 days)

Sunrise today 06:05, sunset 16:21

		Tue, 11/3		Wed, 11/4											Thu, 11/5								Fri, 11/6								Sat, 11/7								Sun, 11/8								Mon, 11/9							Tue, 11/10				Wed, 11/11				Thu, 11/12				Fri, 11/13				Sat, 11/14				Sun, 11/15				Mon, 11/16				Tue, 11/17
Japan time		21	23	1	3	5	7	9	11	13	15	17	19	21	0	3	6	9	12	15	18	21	0	3	6	9	12	15	18	21	0	3	6	9	12	15	18	21	0	3	6	9	12	15	18	21	0	3	6	9	12	15	21	3	9	15	21	3	9	15	21	3	9	15	21	3	9	15	21	3	9	15	21	3	9	15	21	3	9	15	21	3	9	15	21

Temperature	°C	-9°	-9°	-7°	-7°	-6°	-7°	-6°	-5°	-4°	-5°	-9°	-8°	-7°	-8°	-7°	-4°	0°	0°	0°	0°	-1°	-1°	-1°	-2°	0°	2°	1°	-2°	-6°	-8°	-10°	-11°	-10°	-9°	-10°	-11°	-11°	-11°	-11°	-12°	-10°	-9°	-10°	-11°	-12°	-12°	-12°	-12°	-10°	-9°	-10°	-13°	-13°	-10°	-7°	-10°	-9°	-8°	-5°	-10°	-12°	-8°	-7°	-12°	-12°	-12°	-11°	-11°	-14°	-7°	-6°	-9°	-9°	-3°	-3°	-2°	-3°	-2°	-5°	-11°	-12°	-8°	-7°	-12°
Precipitation	mm			0.9	4.8	0.2													0.6	0.4		0.4	2.2	3.4	1.9	3.2	0.6	0.4	2.2	1.0	1.4	1.7	0.8	1.0	1.0	1.2	0.1		0.1	0.7	0.5	0.2	0.4	0.1														2.7	2.9	0.6			0.2	1.1	0.2		0.2	0.1							0.3	0.8	7	1.5	1.6	1.2	0.2
New snow	cm			0.9	4.8	0.2		<.1																						0.2	1.4	1.8	0.9	1.0	1.0	1.2	0.1	<.1	0.1	0.7	0.5	0.2	0.4	0.1	<.1							0.1		<.1				2.7	2.9	0.6			0.2	1.1	0.2	<.1	0.2	0.1	<.1								<.1	0.2	<.1	0.7	0.2	<.1
Snow depth	cm	1	1	1	4	5	5	5	5	4	4	4	4	4	4	4	4	4	3	2	1	1	1	1	<1	<1	<1	<1	0	0	<1	<1	<1	<1	2	2	2	2	3	3	3	3	4	4	4	4	4	4	4	4	4	4	3	3	3	3	3	5	8	8	7	7	7	8	8	8	7	7	7	7	7	7	7	7	7	6	5	5	5	5	5	5	5	5	5
Wind	m/s	3	1	3	4	4	5	5	4	3	1	1	0	1	1	1	1	2	3	1	2	1	1	1	1	1	4	5	7	7	8	7	7	7	8	8	6	6	5	5	5	5	7	6	5	4	3	2	2	3	4	3	2	2	1	1	2	4	2	1	1	1	2	3	2	3	5	5	2	3	2	2	1	1	1	1	2	1	1	3	4	4	3	2	1
Wind gusts	m/s	11	11	11	14	15	17	18	16	14	11	8	5	6	7	8	7	10	11	10	7	7	5	5	6	6	11	16	20	21	23	25	24	25	25	25	22	19	19	19	19	17	19	20	18	16	13	10	9	9	12	12	12	7	7	7	6	13	11	7	4	5	8	11	12	11	16	17	15	11	11	9	7	6	8	9	10	9	5	11	13	14	14	9	6
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