Day 10 - Spokane, Washington plus the Grand Coulee Dam This morning you will have time to visit Penticton’s famous wine country and stop at a leading winery. There will be a tour of the winery and of course a chance to sample their world class wines. On highway 20, which is one of the most spectacular highways in the state of Washington, is the Grand Coulee Dam. This is a must stop for pictures of this 555 foot high, 5,223 foot wide engineering marvel.