This map shows the general topography  - the Tualatin Mountains and Mt. Tabor and then the other buttes in southeast and northeast. You can also see here where the Banfield is - Sullivan's Gulch.  It was created when one of the ice dams broke during the glacial age. Water poured down through here and made created this channel. Since then it has been a convenient place to put a lot of transportation. The other thing you can see from this map is that downtown Portland did have a firm bank - everywhere else, on the east side for instance, where the Central Eastside industrial area is today, was all marsh land and then if you go South from there it's all up on bluffs.