Rail Museum around Ottawa?

I've heard/seen references to a railway museum in or around Ottawa. Searches come up with everything from military to science and technology museums, but no railway museum. Can anyone clear this up? Does it exist? Location, web site, anything?

The Canada Science and Technology Museum has several pieces of preserved railway equipment including a few steam and diesel locomotives among its various exhibits. Most of the museum is devoted to non rail subjects but these are interesting none the less. The Bytown Railway Society has some equipment stored there as well but most is not generally open to the public.

Got it. Many thanks, that's the one my searches kept going to.