PARIS, France: Amid the summer heatwave, the Paris Sewer Museum offers a refreshingly cool and unusual escape. For 22 years, chief sewer engineer Emmanuel Olivard has guided visitors through the museum’s historical and technical exhibits, revealing 500 metres of the 2,500-kilometre sewer network where wastewater and river water flow. His mission is not only to showcase this hidden infrastructure but also to pass on vital knowledge about waste management. Since its reopening in 2021, the museum has welcomed 75,000 visitors each year. – Joseph Grosjean/AFPTV/AFP