The National Gallery contains many interesting and famous pieces, including the "Maman" spider (Louise Bourgeois) out front, the controversial "Voice of Fire" (Barnett Newman), and my two favorites, "Iris" (van Gogh) and "Waterloo Bridge: The Sun in a Fog" (Monet). Visitors are allowed to freely take pictures of the works in the permanent collection, including the European Gallery (the pic of the piece is followed by the pic of the information plackard). I also really liked the Garden Court and Water Court - they were very peaceful and contemplative places.