Organizers said their goal was to be a "huge pain." But though the convoy of hundreds of trucks, cars and SUVs started out moving in a formation that stretched roughly 30 miles, it became diluted after merging with normal Beltway traffic.

As of 1:40 p.m. Sunday, the convoy was beginning its second loop around the District. The vehicles were mostly remaining in a single lane on 495′s outer loop, going around 40 mph. Traffic was flowing around them as usual at about 55 mph.

The demonstration is expected to last for hours as the convoy circles the Beltway a second time before heading back to the Hagerstown Speedway, the protesters' current base.