If you are looking for train-themed accommodation near Olympic National Park in WA (because who isn’t?), I highly recommend the Red Caboose Getaway B&B in Sequim, WA. All of the “rooms” are converted cabooses, each with its own theme. We stayed in the Casey Jones caboose, dedicated to railroad memorabilia. The multi-course breakfast was delicious and served in the “Silver Eagle” dining car, where you can watch birds and ducks in the pond outside (and apparently the occasional bald eagle making off with one of the ducks).
Sequim (pronounced “squim”) is a 20-30 min drive from the Olympic National Park visitor’s center in Port Angeles and can serve as a base for visiting the Hurricane Ridge area and northeastern part of the park. Sequim itself is a small town that is apparently the “Lavender Capital of America” (many lavender and other farms are open to visitors) and home to the 
Dungeness National Wildlife Refuge.