Around the Port everything is labeled “Swantown” and I just got around to looking into why.
Apparently named after one of the first european settlers in Olympia, John Swan, the Swantown Slough is an area that was filled in under, essentially, Plum St. and the remaining East Bay area. The Salish called it Cheetwoot. The original european settler’s city was called Swantown, later to be renamed as Olympia. The west side, originally called Marshville, was reached via a footbridge.
There’s some nice walking trails detailed by Olympia Today. (Which appears not to have an index page? What’s the entry point to this website?) [Update: Emmett O’Connell pointed me to the entry point. He has a newer Olympia Time online, as the old one is stale.] Trail No. 2 talks about the Swantown Slough.
An approximation of the original shoreline is outlined with bronze markers.
Some other references include:
The History of Olympia
Olympia’s History and Resources (HTML cache)
Eastside Neighborhood walk in Olympia, Washington
Mallory v City of Olympia (a case over a sewer construction project in Swantown Slough.)
Historic Preservation Plan (HTML cache)
Olympia 1879 (page with a lithographic image)
Olympia, WA 1917 (JPG image of a map showing old Main / Pacific Highway)
Olympia and Thurston County History
The Olympia Historical Society