Rock Creek Park is the first urban park in the country and twice as big as Central Park, and it’s celebrating its 125th birthday this year. One small nonprofit is trying to make sure it’s around for another 125 years.

The Rock Creek Conservancy, run by Matt Fleischer, is working with the National Park Service on a year-long campaign called “Find Yourself in Rock Creek Park”. It includes a new smartphone app with maps and help finding hiking and biking trails, tributaries, Civil War-era forts, historic mills and recreational facilities. And a Green Ribbon Panel was formed with people from environmental conservation, the arts, business, and lawmakers to figure out what the park needs. The recommendations will be presented to the National Park Service, which runs the 3,000-acre park, in September. (New York's Central Park is 843 acres.)

The Rock Creek Conservancy protects the park’s land and its 33-mile watershed, says Matt. The seven-person team is also working on adding more trailhead signs and designing the future mobile app to have geolocation mapping. That’s the fun stuff. The organization also holds an annual trash cleanup in April that draws over 2,100 volunteers stationed at 77 sites. Matt says they've cleaned up 867 tires and 37,350 plastic bags since 2009. The Conservancy also helped pass the Bag Bill. The charge for plastic bags in DC and Montgomery County has encouraged their reuse, cutting down on the number of bags found in the creek and tributaries. The group also successfully advocated for a ban on polystyrene (used for lots of packaging) in Montgomery County. It had already been banned in DC.

One of the conservancy’s biggest programs is removing English Ivy, a killer of trees. Matt says the goal is to reach 12,500 trees for the 125th birthday, which is technically in September. So far 8,000 have been relieved of English Ivy in the past two years. If the park loses trees, it’ll cut down the tree canopy, which helps cut back on the amount of water that runs off into the creek and sewer, damaging the water quality. The group, funded through individuals, government grants, businesses and foundations, also works with nearby homeowners on creating rain gardens so rainwater doesn’t go into sewers as quickly. Matt says the ultimate goal is to make the creek fishable and swimmable.