PORTLAND, Ore. -- The morning of August 21 will bring a remarkable sight in the sky above Oregon.

The solar eclipse will sweep across Oregon from west to east. The Oregon Department of Transportation expects a crush of travelers who want to see it.

Interactive: View the eclipse from any location

“We could be seeing travelers coming in from Washington. We could see travelers coming up this way from California at that time. We're really on the alert for a major traffic event -- probably nothing like the state has seen before,” said ODOT spokesman Don Hamilton.

ODOT’s advice? Don't try driving on August 21. Get to where ever you hope to watch the eclipse a couple days early -- then settle in and don’t try to leave until the 22nd.

And yes, the agency has thought about all the drivers who want to simply pull off the highway to watch the eclipse as it happens.

“Pulling off the side of the road on a congested highway is a safety danger. That's the danger there, all the roads, we don’t want to stop the roads and that's what that would do. Completely clog up the roads,” said Hamilton

ODOT will have crews on hand to try to keep traffic moving, but remember, especially in central Oregon, there are few services. Go well prepared. You may run into gridlock.

“People who get stuck on the road may not have the supplies they need. They may not have the food and the water that they need if they're stuck in traffic," said Hamilton.