Coming from Boise and heading towards Portland, I first thought my GPS navigation was broken. We entered I-84 and it said "please turn right in 600 kilometers". Nevertheless it was not. The trip there was through some pretty empty region, nevertheless it was still interesting. In the end, there is a long drive along the Columbia River and the Columbia River Gorge - a very nice area with pretty waterfalls.
Portland itself is a nice city with many microbreweries, brewpubs and a relaxed atmosphere. A good decision to have a stop here on our way back to Seattle.