There are a few landmarks that are unique to Portland that folks just have to have in the background of their selfies. The most popular ones right now are the “Keep Portland Weird” sign and the “Portland Oregon/Old Town” sign with a deer on it. These two are right downtown by the waterfront and close to a cluster of things to see, so easy to find. Just a block away from the “Keep Portland Weird” sign is the decorative gate to China Town. Before the other two signs came into being people were standing in front of this Chinese Gate getting their photos taken.
The other selfie spots will take more of an effort to track down. If you are visiting the South Park Blocks to see the Portland Art Museum or the Oregon History Museum the “Salmon Swimming through the brick building” will be just a few blocks away. Pioneer Courthouse Square this is on some peoples lists of a must see and you will find “Umbrella Man” there also. Now “Bart Simpson in the side walk” and the “Large Paul Bunyan Statue” are not close to anything and you will need to make a special journey and effort to find them.
Now if you want a picture with city of Portland in the background the two best spots are at the view point at Pittock Mansion and along the East Bank Esplanade.