The invitation to antique car owners sent out by The Friends of the Historic Columbia River Highway noted that to participate, vehicles must be model year 1949 or older and be 'true' antiques (meaning no hot rods or restore rods). Proper period attire was encouraged. The route took participants from Troutdale to The Dalles along old Highway 30.
After all of them had passed us we drove behind them in hopes to be able to photograph them while they were parked at the Vista House, an old building built on a lookout point where you can see miles in either direction along the Columbia River. They were scrunched into the tiny parking lot that was also shared by tourists. You could see on people's faces that they were surprised and delighted to get something more than a view of the river!
We made sure we left before the tour continued onward. We discussed getting ahead of them and taking some more photos but we realized that we could be very delayed in getting back to our coach.