The Oregon Maritime Museum is located on the Willamette River at Water Front Park on board the historic sternwheeler Portland. Years ago it was locate in one of the old cast iron front old town building but rent got to high so they move it on board. There website does a good job of explain the place:
Experience the adventure of life on our rivers when you explore the sternwheeler Portland, the last operating steam-powered sternwheel tug in the U.S. Portland is on the National Registry of Historic Places. The vessel uses the same technology as those at the turn of the 20th century, as evident when you tour the engine room. Volunteer docents will take you on a tour of the steamer, including the pilot house and engine room, and tell stories of the local rivers and their maritime history.
Discover ship models, maritime artifacts and memorabilia. See objects and displays that relate to steam power, sailing vessels, battleship Oregon, underwater diving, and the shipyards during WWII that built the liberty ships and the merchant marines who sailed them.