Visiting a Japanese onsen (also known as a hot spring or public bath) is a relaxing and therapeutic way to spend a few hours (or an entire day! In Japan, people go to an onsen to relax, to meet with friends (and yes, hang around and chat or watch TV while soaking naked in the water) or just to get clean.

There are many different types of onsen or public baths.

It shook so violently that I was afraid the whole thing might smash down on the ground." Other skiers said rocks as big as lunch boxes rained down.

Although not required, 99.9% of people who visit a hot spring in Japan get nude. bathing in onsen is a tradition in Japan dating back hundreds, perhaps thousands of years ago.

No-one stares at your “bits” and really, if you do wear clothing you will be the odd one out. Being the nature of Japanese people in general (i.e. Usually there are several arranged in various areas, indoors and/or outdoors.

A rest house at the resort was hit by volcanic rocks, resort official Yasuaki Morita said. The area is known for Kusatsu Onsen, a famous hot spring resort.

Kusatsu town officials said the impact of volcanic eruption was apparently limited to the ski resort, with no ash or volcanic rocks detected in the town, about 5 (3 miles) from the volcano.

I have been to some onsen, where you sit outdoors (surrounded by a large fence) and bathe in natural rock formations. If it is not a natural hot spring, they will usually mimic a natural rock formation setting.

Some have large single person rock tubs to sit in, rock seats where water pours down your back, rock “beds” where you are semi-submerged in water and tatami mat area to lay on and dry off. Don’t splash or jump into a hot bath, especially if someone is already in there!

Town officials said everyone on the mountain had been accounted for, and all of about 80 skiers who took refuge at a gondola station at the top of the ski slope were brought down to the foot of the mountain, some by a military helicopter, others by snowmobiles. NHK public television showed the first group of rescued skiers, wearing helmets, being handed a bottle of tea each and escorted into a cabin.

"I was scared to death, and I'm so relieved to come back alive," an unidentified male skier told NHK, still wearing a helmet.

Once you are finished, and this can take anywhere from 2 – 3 or more hours, head to the area where you first rinsed yourself off, before the showers.

Rinse yourself off again and then pat yourself down with your small towel.

Japan sits on the Pacific "Ring of Fire" and is prone to earthquakes and volcanic eruptions.