This is cool to see. I used to run past that island all the time whilst doing long runs on the C&O canal trail. I noticed the little ferry and always assumed there was something of interest on the island itself. I also never realized I was far enough north from the city to be directly across the river from the CIA.
On the CIA side of the river there's another trail (Potomac Heritage trail). I was always surprised that you could freely run in the woods there so close to the CIA but also that you could see no sign of their "campus" from the trail.
Full disclosure, I lived on the island part-time for 10 years. There's a stationary rope affixed to the mainland and to a tree on the island. You get there (and back) by pulling the little ferry hand-over-hand along the rope. It was my commuter vehicle.
There was a lot of unmediated information. :) Perhaps we passed each other on the trail.
On the CIA side of the river there's another trail (Potomac Heritage trail). I was always surprised that you could freely run in the woods there so close to the CIA but also that you could see no sign of their "campus" from the trail.