November Project is a group of really awesome people who meet on Mondays, Wednesdays, and Fridays at 5:30 or 6:30 a.m. for a (free) 30-45 minute workout. The DC chapter was formed in 2013 by 2 guys who were originally from Boston (where November Project was actually born). They started this movement to inspire people to get outside and stay in shape in New England during the cold winter months.
The DC branch is particularly great because they take full advantage of DC’s surroundings. On Mondays, they run and do bodyweight exercises at Meridian Hill Park (except for the first Monday of the month where they meet at Capitol Hill). On Wednesdays, they run the stairs of the Lincoln Memorial and break up some of the running with some more bodyweight exercises. On Fridays, the group explores the city and visits a new part of the District each week.
Everyone is very welcoming and alive despite being some of the first people awake in the District. If you are looking for a fun, short, motivating workout that is free, I highly recommend November Project!