Pro tip: get in line sufficiently before closing time that you are guaranteed entry. Proceed through the first few rooms, then loiter. Move much slower than the horde of crowds flowing through the halls. Spend an hour looking through the early exhibits (I could spend a day in the room of tapestry maps alone), until the entrance is closed and the crowd thins. Make your way to the chapel and enjoy until they kick you out - I was in there for 15 minutes with just a few other people! (Albeit in October, not "peak" season).