The train is operated by AMTRAK. It departs Seattle 7:45am from the station downtown, arriving in Vancouver at 11:40am. It is the most beautiful ride, right along the water's edge in many places. I recommend it. It returns from Vancouver in the evening.
The adult fare is $34.00 one way.
They have bus service as well between the two cities.
Check with AMTRAK for more info. Their website is very helpful.
Hope this helps.
CruiseMates Contributing Editor