Mori Art Museum, located on top of a 54-storey skyscraper in Roppongi, is the metaphorical giant of the Tokyoite art, and the one gallery you should not miss out on during your art tour! The museum hosts numerous, diverse, themed exhibitions and shows that range from cerebral to eccentric, their website provides information on current exhibitions and show times. The museum is open from 10am to 10pm daily but closes at 5pm on Tuesdays. Ticket prices vary and can also be found on their website. Don't forget to go out onto observation deck once you're done exploring the museum, the breathtaking, 360-degree, panoramic view of the Tokyo the deck provides is unrivalled.