National Gallery

From the Wikipedia page :

The National Gallery is an art museum on Trafalgar Square. Founded in 1824, it houses a collection of over 2,300 paintings dating from the mid-13th century to 1900. The gallery is an exempt charity, and a non-departmental public body of the Department for Culture, Media and Sport. Its collection belongs to the public of the United Kingdom and entry to the main collection (though not some special exhibitions) is free of charge.

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