Hi- thought I'd chime (tweet) in: one of my favorite morning walks (before joggers & dog walkers, bikers) is Aspen Hill in Rockville which is part of Rock Creek valley stream park.
It is a paved path that winds up past Lake Frank and Lake Needwood. Good seasons are Spring and Fall, but winter is delightful too. There is a section about these lakes and trails in the MOCO birders guide.
 
D.Ford/Bethesda, Md