Ostrava, Czechia

Ostrava is the third-largest city in Czechia, with around 285,000 residents living at the confluence of the Ostravice, Oder and Opava rivers. Coal discovered here in 1763 drove steel and iron production through the 20th century, shaping the city's industrial landscape. The Lower Vítkovice area, founded in 1828, preserves blast furnaces, a gas holder and mines as a national cultural monument and a UNESCO candidate site. The 1531 Ostravice wooden bridge historically linked Moravia and Silesia, while the multicolour Nová Karolina coal seam reaches roughly 30 metres thick. What remains hidden beneath this surface still draws geologists today.