The Northwestern United States is an informal geographic region of the United States consisting of Washington, Oregon, Idaho, Montana and Wyoming. The Pacific Northwest is best known for its beautiful coastline, green interior, rainy weather, and spectacular mountains. Idaho is a rugged state with snow-capped mountains, whitewater rivers and plenty of wilderness. Montana is a state of contrasts, from the flat regions to the east and the towering peaks of the Rocky Mountains in the west. Wyoming offers a wealth of outdoor recreation and sightseeing opportunities, including Yellowstone National Park.