2. The National Gallery London, England
www.nationalgallery.org.uk
Britain's national art museum and Trafalgar Square landmark is a favorite with travelers for its organization and friendly staff. Best of all, admission to the museum is free because the collection is considered to belong to the British public. It's not every day an art museum is so visitor-friendly and enthusiastic, particularly one with such a prestigious array of masterpieces.
The permanent collection's focus is Western European paintings from 1250 to 1900 and you'll find great works representative of nearly every period in art history by masters from Botticelli to Monet.