The Danube always played a significant role in the city life of Budapest, or Pest, Buda, and Óbuda before 1973. The powerful river was not always friendly, as it used to flood the city which caused severe damage, especially on the flat Pest side.
If you wander around the city you may notice plaques with water markers set in stone at different levels. The majority of them refer to the most devastating flood of March of 1938 when water levels reached up to 2,6 meters high and several kilometers deep into Pest. You can see the whole map of the flooded areas during its first days on this memorial plaque in Egyetemi sq. Even though the watermarks are subtle and hard to notice, the flood was far away from being understated: a lot of people died, 50.000 residents lost their homes, 2485 (2281 in Pest only) houses collapsed and 1089 buildings were severely damaged.
This event had a huge influence on the city’s face and structure, as it cleared up space for the new buildings and neighborhoods, and inspired better water management projects that include not only restricting the Danube stream and reinforcement of its banks but better drainage system. The city was reborn as a Phoenix, and became stronger and better prepared for possible natural disasters.
Searching for the watermarks can be an exciting quest, this website with the images and addresses can help you identify them. In any case, now if you see one, you will know what it refers to.