The Tri-Met system is an efficient and simple way to travel around Portland without ever needing a car. We got off the plane, walked out of the airport and out to the Max light rail terminal. There we met with the only glitch in the system. We were staying 3 days, and wanted to buy a 3-day pass. There are vending machines right in the station, but they do not sell passes, only 1-trip tickets and Quik-Tik 6-hour tickets. To buy a pass, you have to go downtown. So you have to buy a ticket in order to buy a pass that would have been good from the airport, if only it had been available at the airport. In addition, the machine does not take dollar bills, only dollar coins. However, a very helpful attendant gave us the dollar coins we needed to buy our Quik-Tiks, which we used for the rest of the day.
The Max light rail runs into the downtown area, and dropped us off just a few blocks from our hotel, about a 35-minute ride.
In the downtown area, you can travel for free in the area bounded by the Willamette River, NW Irving, and the I-405 freeway, as well as riding across the Steel Bridge to the Lloyd District (including the light rail stops at the Rose Quarter, Convention Center, NE 7th Ave and Lloyd Center shopping mall) -- it is known as the Fareless Square. Public transportation is user-friendly; the Max has the next stop prominently displayed on lighted signboards in all the cars, as do most buses.
The Tri-Met website is also user-friendly, with maps of bus routes and a route-planner. A single two-zone fare is $1.45, a Quik-Tik is $3, a one-day pass is $4, and a three-day pass is $10.