Number 90 - Tom, as others have already said ( paraphrasing here ) the B&O Museum is truly wonderful! It houses the first train station, Mount Clare Station, of a US common carrier railroad. The first scheduled train to ever depart within the US departed from Mt. Clare Station, which is housed within the museum. The famous race between the horse drawn carriage and the Tom Thumb locomotive started here at Mt. Clare. I believe, and I could be wrong but, the first telegraph message " what hath God wrought" originating in Washington DC sent by Morris was received at this station ( transmitted through wires alongside the Washington branch of the B&O ) as well. As you already know there is LOTS of history here.
As a member of the B&O museum for many years, I've seen nothing but improvements over the years, especially since the B&O Museum and the Smithsonian have partnered.
The display of equipment is quite remarkable! The old 19th century pieces within the roundhouse are in immaculate shape. If you choose to do so, you can ride the museum train over the first mile of common carrier railroad in the US. And yes there are some pieces of equipment in the front of the museum that need some restorative work. I'm confident that the museum management, staff, and volunteers will get to those pieces when time, facilities, and money become available.
There is one piece of equipment, Pennsy GG 1 number 4876, that sits rusting away. It can be viewed on the train ride along the first mile. I wish the B&O Museum would do cosmetic restoration. This was the engine that pulled the Federal from Boston with passengers coming to attend Eisenhower's inaugural in January 1953. The train lost it's brakes and crashed through the bumping post and into the main concourse of Washington's Union Station as I'm sure you know this story. This engine was cut up into pieces, removed from Union Station, put on flat cars, taken back to Altoona, reassembled, and was back out on the mainline pulling trains by the end of 1953.... quite remarkable! The last time I inquired with museum there were no plans to cosmetically restore 4876.
While you are here, you may also want to check out the first railway terminus in Ellicott City, Maryland. This station is also part of the B&O Museum and your price of addmission paid in Baltimore will also get you into this museum as well. While there really isn't any equipment except for a caboose, there is alot of history that compliments the bigger museum in Baltimore.
Drop me an e mail and let me know when you are coming to town. If our schedules permits (mine tends to be extra full in the spring ) perhaps we can meet up. My e mail is in my profile.
Enjoy your trip Tom!