Thanks to everyone who posted about this. I went there today.
For those who might still want to go, here is a summary:
There are active Cliff Swallow nests on both the north and south sides of the
bridge.
The north side is accessible from Bull Run Marina, which is public. It is
operated by the Northern Virginia Regional Park Authority, and there are a
couple parking lots intended for those with boats. The lots were pretty empty
today, however. Here is the website:
https://www.novaparks.com/parks/bull-run-marina
The south side is accessible from the trail on the south side of the road.
There is a large public parking lot as others have mentioned. Walk on the paved
trail down to the river; where the blacktop trail ends, keep going to the right
(north) on the dirt trail. Stop before you get to the boulders. You can easily
see the nests from there.
There is no need to climb on any boulders. (They are under the bridge abutment
and a little beyond on each end.)
Obviously, be careful crossing the road on foot if you choose to do so!
Other highlights today were singing Northern Parula, Yellow-billed Cuckoo, and
White-eyed Vireo.
Claire Kluskens
Fairfax Co.
