I'm glad I decided to walk to the Kuniyoshi exhibition at Roppongi Hills from my hotel in Toranomon as on the way I discovered this amazing building - Reiyukai Shakaden.
Nearest station is Kamiyacho and it's open to the public - so long as you're brave enough to go through the 2 sets of big heavy doors at the top of the stairs! I felt like I was entering an alien spaceship!
The Kuniyoshi exhibition was also spectacular. It's on until 12th Feb.