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Review Highlights
Interesting for a quick stop by

The fumes released from the ground was much more voluminous than expected and so was the stink... read more

Reviewed 15 October 2018
via mobile
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 23 August 2018
Singapore, Singapore
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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
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All reviews active volcano sulphur vents boiled eggs parking fee car park live volcano boiling hot water volcanic activity lake mashu beautiful scenery souvenir shop steam smell yellow ground rocks geology
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1 - 10 of 53 reviews
Reviewed 15 October 2018 via mobile

The fumes released from the ground was much more voluminous than expected and so was the stink. Worthwhile for a quick stopover as it’s close to the car park. Parking fee of Y500 is shared with Lake Mashu Observation Point 1.

Thank P T
Reviewed 23 August 2018

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

1  Thank cphilip98
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 JohnD209
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 10 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 7 April 2018

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

Thank pollyoppy
Reviewed 27 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 20 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
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