The Louvre is probably the most famous of all art galleries in the world - whilst the Guggenheim is the most widespread. Between them they house some of the finest art from Ancient Egypt to the present day.
The Louvre, in Paris, was originally a fortress, built in the 12th century. It was converted into a royal residence 400 years later and was decorated with many great artworks such as The Mona Lisa.
Following the French Revolution the Louvre became a museum, opening its doors in 1793. Over the following centuries its collection has grown, helped in part by the conquests of Napoleon.