A prolonged drought has pushed the Danube River to record-low levels, revealing long-submerged relics

Several sunken World War II-era Nazi warships have resurfaced in the Danube River amid a major heatwave and prolonged drought. The vessels became visible as the water level in Europe’s second-longest river fell to record lows.

Photos and videos posted on social media showed massive shipwrecks lying in the water and on a sand ridge in the middle of the waterway near the village of Prahovo in Serbia.

Elsewhere, the wreck of a Hungarian cargo ship that sank in 1937 resurfaced near the Croatian village of Opatovac.

Some 200 vessels could be lying on the bottom of the Danube River, according to the European Investment Bank. River transport has nearly come to a halt due to the low water levels, according to Hungary’s Transport Ministry.