In article , wrote:

My wife and I were in Portland just last month for a business trip. It is a
beautiful city, and the public transportation is unbelieveable. From PDX
you can take a "MAX" train into town, and get to Troutdale via MAX to
Gresham then jump on a city bus which will get you within a block or two of
the airport. Tickets for both the trains and busses for two hours were $2,
and an all day pass was $4. It's an incredible bargain, and the trains and
busses were some of the cleanest and best maintained I've ever ridden on.
We didn't have time to get checked out and rent a plane, but we are planning
a return trip someday.

There is a stop for HIO/Hillsboro, also.