Why is "1964 Zagreb flood" trending?

Wikipedia Overview

On 25 October 1964, a devastating flood of the River Sava struck Zagreb, SR Croatia, SFR Yugoslavia. High rainfall upriver caused rivers and streams in the Sava catchment basin to swell and spill over their banks in many places throughout Slovenia and northern Croatia. The worst of the flooding occurred in Zagreb. Sava floods were a known hazard in the city, having affected the development of the area since the Roman times, and the 1964 flood did not have the largest extent. However, it occurred following several decades of large-scale industrialisation and urban growth which had caused the city to expand into the most flood-vulnerable areas. The quality of building construction and flood defences in the floodplain was mostly low. Regulation of the Sava and its tributaries upriver from Zagreb cut off many natural detention basins, such as fields and pastures, which caused water to pile up ahead of the city. To make matters worse, the soil was already saturated from a mid-month episode of fairly high rainfall. A second episode of high rainfall, during 22–25 October upriver in Slovenia, produced a record-high water wave in the Sava. At Zagreb's Sava River gauge, the water crested at 514 cm above zero level, exceeding the previous high water mark by more than half a metre (2 ft). This proved too much for the city's embankments. Around 60 km2 (23 sq mi) of the city was flooded, including most neighbourhoods on the western side of the floodplain.