For most of the day people were out digging holes in the road at Wisconsin Avenue and East-West Highway in Bethesda, MD. They had a lane of traffic blocked of on each of those roads during the middle of the day. It looks to me like they still have work to do so I expect they will be back today.
The question is "What are they doing?" I think I know. There are lots of orange lines painted on the road and alongside the road and many of them have a little flag that says "AboveNet, Caution, Fiber Optic Cable Buried Below" I think they are putting in some new fiber.
I also saw the flags on Montgomery Lane near Arlington Road so they may be in the area for a few days with this project.