The Mountain Loop trail on Sugarloaf Mountain (only 40 minutes outside of D.C.) is a great close-to-home hike. The uphills are only short bursts across six miles with a spectacular view of the valley at White Rocks. And you can stop for a post-hike drink at the Sugarloaf Mountain vineyard.
Within reasonable driving distance from D.C., the hike to Annapolis Rocks on the Appalachian Trail is a popular hike. My legs and my lungs usually feel the first two miles of uphill and then enjoy the level trail. The viewpoint, especially when there are bear sightings, is totally worth the early huffing and puffing.
Most of my adventures happen on two feet but occasionally two wheels are involved! I took a scooter ride through the winding roads of Montgomery County to Point of Red Rocks in southern Frederick County. The iconic graffiti covered spot is famous and popular among hikers, climbers, motorcyclists, and ice cream lovers! So a perfect spot to head to on a hot day.