The only way to access the Gunnison River from the park by car is via this paved route, which drops approximately 2,000 feet down to the water in only 5 miles, giving it an extremely steep grade. Vehicles longer than 22 feet are not allowed on the road. If you're towing a trailer, you can unhitch it near the entrance to South Rim campground. The bottom of the road is actually in the adjacent Curecanti National Recreation Area. A tour of East Portal Road, with a brief stop at the bottom, takes about 45 minutes.