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Review Highlights
Nice stop between Lake Mashu & Lake Kussharo

This place is in the middle between the two lakes. If you are around here, you should drop by to... read more

Reviewed 4 weeks ago
Singapore, Singapore
Glow-in-the-dark yellow sulfur hills

Iouzan – Iouzan, or Mount Iou, is an active volcano located on Hwy 52 between Lake Mashu and Lake... read more

Reviewed 11 August 2018
John D
Leavenworth, Kansas
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  • Excellent33%
  • Very good45%
  • Average19%
  • Poor2%
  • Terrible1%
Travellers talk about
“sulphur vents”(4 reviews)
“boiled eggs”(4 reviews)
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Teshikaga-cho, Kawakami-gun, Hokkaido
Reviews (385)
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All reviewsactive volcanosulphur ventsboiled eggslive volcanoboiling hot watervolcanic activitylake mashucar parkparking feebeautiful scenerysouvenir shopsteamsmellyellowgroundrocksmount
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1 - 10 of 52 reviews
Reviewed 4 weeks ago

This place is in the middle between the two lakes. If you are around here, you should drop by to take a look. When first got out of the car, the strong sulphur smell would welcome you. You can walk very close to where the...More

Thank PhilipC2626
Reviewed 11 August 2018

Iouzan – Iouzan, or Mount Iou, is an active volcano located on Hwy 52 between Lake Mashu and Lake Kussharo; the nearest train station is the Kawayu Onsen Station, about a mile from the Iouzan resthouse. You cannot climb to the top of the volcano,...More

Thank John D
Reviewed 17 July 2018

Interesting Sulphur spewing live volcano you can come up close with through a very short walk from the car park. You can see, smell and hear the live volcano in action.

Thank Khaykid
Reviewed 23 June 2018

you can stop and pay to park or do what we did - parked at Kawayu visitor centre and walked 2 km each way through the woods, which was very pleasant

1  Thank 769John
Reviewed 8 May 2018 via mobile

Beautiful and astonishing... Really feel the power of our beautiful planet. We all enjoyed. Parking, souvenirs, restaurant and toilets available. The smell is a bit repulsive at the beginning (like roted egg) but gets better as soon as you get closer to the hot springs...More

1  Thank Bruno B
Reviewed 9 April 2018

The first thing that will get you at Mount Io is the parking charge - just before the sulphur smells LOL. From what I remember it was JPY500 or JPY600 (maybe JPY200 for motocyles). However this is a joint parking fee with Lake Mashu 1st...More

1  Thank plunet
Reviewed 6 April 2018

Well worth a side trip if you are passing. The mountain is very impressive with sulphur and bubbling water.

Thank pollyoppy
Reviewed 26 March 2018 via mobile

It feels weird to know that it's a live volcano that we are stepping on and every where you would see steam gushing out from the ground with the smell of sulphur all around! It's a great experience and sight!

Thank alanyeo76
Reviewed 19 March 2018

Wonderful at any time of year, it is perhaps most impressive on a cold winter's day when the wind is pushing the steam from the sulphur vents away up the valley.

Thank StellersEagle
Reviewed 6 January 2018 via mobile

This place was so amazing that the memory of the moment I stepped foot on this active volcano with the clouds of steam and the sulfur smell bursting their way through my sinuses, still haunts me, in a very very good way. We came here...More

Thank Mohammed1412
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