While on a business trip to Washington DC, I took a side trip to Occoquan Bay NWR and Huntley Meadows in northern Virginia. Being April 25, it was a bit early for peak migration, but there were migrants trickling in.
Both locations were very nice with plenty of paths and natural habitat, and I'd highly recommend both for traveling birders or nature lovers.
Occoquan Bay NWR is on the Potomac (the Potomac is quite wide as you proceed southward from DC). It has meadows, forests, and some water habitat, though I didn't see any real shorebird habitat.
Osprey were the birds of the day at Occoquan, with numerous seen perching, flying, and fishing. This photo shows one near its typical large nest. I couldn't detect any young in the nest.
There were a mix of warblers and vireos, too. Common Yellowthroat, Prothonotary, Northern Parula, and Yellow Warbler were all noted. This Prothonotary was singing on a prominent perch:
Not many butterflies were seen (it was a cool day with an occasional sprinkle or shower). However, there were a few Eastern Tailed Blues:
Oh, and while Turkey Vultures aren't exactly uncommon, this one was certainly uncommon in that it let me approach very closely.
Huntley Meadows is an inland park south of Alexandria containing a mix of meadows, forest, and wetlands. The wetland area had a large boardwalk, and was the highlight of the park the day I was there. Along the boardwalk, several frog species, a turtle, and a raccoon were seen, along with numerous birds.
This raccoon was wondering towards me for a minute or two before finally realizing I was there - which startled it and caused it to run away.
This Great Egret confirms that yes, this is a wetland.
I found this head-on Common Yellowthroat photo interesting. It's not the classic look with an eye catch, but it shows the coloration in a unique way.