♨️onsen water types, ranked by what helped my legs

Not the famous ones necessarily. What worked, after actual hikes.

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Sulfate springs (硫酸塩泉)

Boring name, does the most for actual muscle pain. Anti-inflammatory, not just warm water. This is the one, not the famous smelly one below.

Chloride springs (塩化物泉)

salt clings to your skin and you stay warm long after you get out. good for cold nights, less for soreness itself.

Sodium bicarbonate springs (炭酸水素塩泉)

Softens everything, feels almost slippery. Nice, but did nothing for my calves after Kumano Kodo.

Simple springs (単純温泉, alkaline)

gentle enough for every age, which is also the problem. pleasant, forgettable.

Iron-bearing springs (含鉄泉)

turns rust-orange in the air, stains towels, genuinely warming though.

Acidic springs (酸性泉)

Sulfur springs (硫黄泉)

Everyone's favorite for the smell and milky water, lovely for skin. Did nothing for my legs after Yakushima. Ranked last anyway.

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