Rotterdam was quickly rebuild after the war, but modernization led to the fact that many old buildings were not repaired, but replaced by totally new ones. The has led to the fact that the centre of Rotterdam is composed of new buildings, a thing not common in European city's. The ports of Rotterdam grow even more during the latter part of the 20th century. New area's, build right in the sea are "Botlek", "Maasvlakte", and "Europoort". The Euromast (185 m high) becomes an icon of Rotterdam. De metro of Rotterdam is opened in 1968, which then is the first metro in the Netherlands. The 1990s saw an increase of skyscrapers. The "Delftse Poort" which was ready in 1991 was the highest skyscraper in the Netherlands, with 151 m high, until the "Maastoren" became the highest building in 2009 with 165 m. The new Erasmusbridge which was ready in 1996 gave Rotterdam a new symbol.