About the closest rail-related attraction to your hotel is the B&O Museum on Pratt Street.  Lots of awesome prototype stuff to see there!  If you don't mind driving or taking the Metro, you could visit MB Klein's (a.k.a. modeltrainstuff.com) in Cockeysville. 

I wish my layout was still standing, then I could've invited you for an op session.

 The B&O museum, of course.  www.borail.org

I lived in the area (Ft. Meade) for a couple of years and if you have the time I recommend hopping on the water taxi down at the inner harbor and taking it all the way around the system, perhaps hopping off and back on at some of the shopping/tourist areas. It's a great way to see a part of Baltimore that many don't.

Also, from the Model Railroad perspective, Peachcreek Shops is just down 295 in Laurel, MD.

You might also just hop on the light rail and take it from end to end - when I lived there it went between the north end of Glen Burnie south of Baltimore and the Maryland State Fairgrounds (which is where I believe the Great Model Train Show will be) to the north.

but I checked out the B&O museum website, and their hours are shorter than my conference times, so its unlikely I'll be able to make it, unless I can squeeze it in before I have to go to the airport Friday afternoon. It would have been very nice to stay until Sunday, but it hasn't worked out.  Was a last minute thing (literally, at 7:30 this morning I had no idea I was going). 

Dave,

since I'm about 45 minutes down the road in far western Prince George's County (literally across the street from DC), welcome!  I would have added a few things sooner, but I was on vacation myself until last night.

I did a quick check of my railroad happenings calendars, and sadly there's no mid week stuff you might grab. There is great railfanning, and I can link you to a couple of guys i fyou still have time.

Philip

I managed to sneak a visit to the B&O museum today.  Very cool.  My favourite parts were the large E8 model that has the side "cut out" to show the inner workings of the loco, and the C&O Hudson they have in the shop.  

I think the only time I really have will be about 3-4 hours Friday afternoon before I catch the plane home, so I'm not sure what I can accomplish at that point and what I'll do with my luggage after checking out.  Thought about checking out MB Klein's, but I don't think I'd have enough time.