Singapore is one of the best planned urban and cleanest metropolitan cities in the world. It looks like an architectural city model come to life. The city skyline is sculpted to create a unique three-dimensional layer effect. Most of the developments are high rise and high density, so that land is used efficiently. The buildings cannot be higher than 280 metres due to air traffic control restrictions, but that has added a tall (but not too tall) and consistent building height and space pattern that makes this skyline unique. The three taller buildings are Republic Plaza, UOB Plaza and OUB Centre exactly 280 metres. The buildings are mostly light-coloured and there is a large expanse of greenery dotted around the city core. This South-East Asia city is definitely in a league of its own.