The extreme eastern section of Oregon in the Snake River Valley, including Ontario, is part of the Treasure Valley, which extends east to Boise, Idaho; unlike the rest of the state, that section lies within the Mountain Time Zone.
The extreme eastern section of Oregon in the Snake River Valley is part of the Treasure Valley. This is including Ontario. The Treasure Valley extends east to Boise, Idaho. That section lies within the Mountain Time Zone. This is unlike the rest of the state.