Rolling Thunder

I know this is a week late, but here it is anyways.
Every year on Memorial Day, Washington D.C. plays host to the Rolling Thunder. Over 300,000 bikers converge into D.C. to pay their respects and to participate in different events. On the day before they rode from Arlington Cemetery and did a loop around the mall. Pretty impressive to watch a several-hour long parade with 300,000+ motorcycles.