We took a tour last year and it was really nice. The ride was a few hours and our guide gave us a lot of info on the history of the gorge. The views were amazing. I recommend dressing in layers with a windbreaker included. It was a nice day but the weather changed frequently while we were there going from sunny and slightly breezy to windy, overcast and misty.
Didn't get to take the tour because it was full when we arrived. They have lots of great beers and delicious pub food. The salmon fish and chips were life changing for my boyfriend.
So good! I highly recommend stopping down the street at Stumptown for a coffee while you wait (especially if it's chilly and misty like it was the day we stopped). Worth the hour long wait. Just make sure you check the menu before you get to the counter. It gets overwhelming looking at all the choices.