When did Lighthouses Come into Use?

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A light house is a tall tower that throws light for guiding sailors at night. This light is quite bright and can be seen from a distance of many kilometres. The light houses are usually built on rocks or islands near harbours and ports and are quite strongly built to withstand storms and sea waves. The first light house probably dates back to 660 B.C. that stood on the coast near Troy in Asia Minor. The lighthouse of Pharos at Alexandria, built in 280 B.C., was one of the seven wonders of the world. It stood for 1500 years, but got destroyed by an earthquake in the 13th century. It used to have fire burning at its top and was 130 m high. Lighthouses now have distinct colour and shapes so that navigators can make out which place they are approaching. They have been built at harbour entrances to indicate the entrance; sunken reef areas; or dangerous sand banks, etc.

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