Sapporo City Sewage Science Museum

The Sapporo City Sewage Science Museum guide asks a question you may never have considered: who actually cleans the wastewater of a city of nearly two million people? Inside the Soseigawa Water Recycling Plaza, you'll meet the tardigrades and ciliates living in the sludge tanks, the real workforce digesting what flows in from every toilet and sink across Sapporo. The guide also follows the leftover sludge to two furnaces that burn it down and put its heat to work, and traces how the city uses warm sewage running beneath its streets through the long winter months. Look for the manhole covers outside, stamped with the clock tower and a salmon.