Flooding has been a part of Venice since ancient times. Between autumn and spring, the city is affected by bouts of periodic flooding known as aqua alta, or “high water”, caused by a combination of astronomical tides, seasonal rain and strong winds, that pushes flood tides into the Venetian lagoon from the Adriatic sea submerging the lowest parts of the city for three to four hours. During these periods, wooden benches are placed end to end to create temporary raised walkways, and business block their doorways until the waters subsides. Although the city has adapted to flooding remarkably well, their instances have become more frequent and more severe in the last few decades. Partly at blame are rising sea levels, but the city itself is sinking.