By bus
Greyhound (http://www.greyhound.com) provides bus service along the West coast as well as from points inland. The depot is located at 550 NW 6th Avenue, across the street from Union Station.
BoltBus, (http://www.boltbus.com). Service from Seattle, WA and Vancouver, BC. Bus stop is at 647 SW Salmon St. Fares $1-20.
By plane
Portland International Airport IATA: PDX (http://www.flypdx.com) is located 9 mi 15 km northeast of downtown on the Columbia River. This is also a dual-use air force base, which can cause confusion on some maps. Most major airlines serve Portland from nearly all major airports in the United States. Non-stop air service is also available from Vancouver, British Columbia, and Toronto, Ontario, Canada; Tokyo, Japan; and Amsterdam. Daily direct service is also available to Pusan, Korea. The airport has free wi-fi.
To travel from the airport to downtown:
A taxi from the airport will cost around $30.
The MAX light rail red line (http://trimet.org/schedul...), costs $2.50 with a free transfer to the bus system and takes 30 minutes to travel from the airport to downtown. The last red line light rail leaves the airport at 11:49PM daily.
By car, the best way to get to downtown Portland from the airport is to take I-205 south to I-84 west, then follow the signs to the City Center at I-84's terminus and interchange with I-5. This will take you over the Morrison Bridge into downtown. When returning a rental car to the airport, follow the signs to stay in the left lane. However, it is very easy to make the mistake of exiting too soon at the control tower/shuttle bus exit. You need to curve to the right with the rest of the highway and not go straight. Even in light traffic, it is dangerous and illegal to immediately turn around.
Important Note Concerning Rental Car Returns: If you need to fill up your rental car's gas tank before returning it, be advised there are no gas stations in the commercial area between the airport and Interstate 205 Cascade Station. If you are heading north on 205, take the Sandy/Killingsworth Exit 23-A exit for the closest and most accessible gas stations to the airport.
By ship
No useful boat lines exist, although you can take cruises up and down the Willamette River.
By train
Amtrak (http://www.amtrak.com/) provides service from Union Station, 800 NW Sixth Avenue north of downtown, about a 15-min walk from Pioneer Square. The transit mall ends at Union Station, so local TriMet buses and the MAX green and yellow lines run by Union Station very frequently.
The Amtrak Cascades (http://www.amtrakcascades.com/) service runs two trains per day between Portland and Eugene to the south and four trains between Portland and Seattle to the north, with one of those going further north to Vancouver, BC. These trains are more reliable schedule-wise than the long distance trains and offer certain amenities not available on regular Amtrak trains, such as more space for bikes, more laptop outlets, a "Bistro Car" which serves local foods and wine, and the occasional movie.
For long distance service, Portland is served daily by the Coast Starlight, running the length of the West Coast Seattle-Portland-San Francisco Bay Area-Los Angeles. The Starlight has earned the nickname the "Starlate", since it is usually delayed for hours running north from California. The Empire Builder Portland-Spokane-Glacier Nat'l Park-Minneapolis/St Paul-Milwaukee-Chicago also provides daily service eastward, and tends not to be as delayed as the Starlight.
By car
From Washington to the north and California as well as most of the rest of Oregon to the south, the easiest way to get to Portland is on Interstate 5. You can enter the south part of downtown from I-5 before it goes over the Willamette River, or you can take I-405 which runs directly through downtown Portland with a number of exits.
From Boise and other points east, Interstate 84 leads along the Columbia into Portland. From the Oregon Coast Highway and other points along the Pacific coast to the west, the easiest approach is U.S. 26. It cuts east towards Portland between Cannon Beach and Seaside.
As with all of Oregon, there are no self-serve gas stations in Portland; an attendant will do the pumping for you.