I have run this race 7 times and it never disappoints. You can't beat rounding the first corner and seeing the Pentagon expanse in front of you. Not only is this race in commemoration of the first responders of 9/11, the race is extremely well run and the post-race party is
Marine Corps Marathon
Loved the course and the crowds. Only complaint - not enough water stops especially around the bridge, and running out of cups in Crystal City was horrible. Overall though, it was a very impressive event and I would recommend it to anyone.
RBC Brooklyn Half
Good half but annoying pre-race logistics
Great course. I know people complained about the location of the number pickup. Unless you live in Dumbo, the pickup location is pretty out of the way. This is the first run I know about where the race organizers let you send a "proxy" to pickup your number