Was at the National Museum of the USAF in October, the B-36 is in the Cold War collection hangar. Along with the other bombers and fighters of the era, just magnificent collection. Also, it's inside (Dayton in the winter is cold!). Getting inside any of their collection is nearly impossible. Either VIP connections or as part of a veterans' gathering is about the only way I know to get interior access to any of the aircraft.
SAC Museum's big collection was outside the last time I was there, but that was many years ago. Omaha in the winter is a repeat of the above temps!
Oh, I see another reply says the aircraft are now indoors. SAC has a Vulcan, however.
Dayton is a short flight away (about an 8 hour drive) from the Air & Space Museum located at Dulles Airport and the original location in downtown DC.