What do you think that Rock Creek Park runs through for mile after mile after mile?
Woods? Cow pastures? Corn fields? A dry lake bed?
No. Rock Creek Park runs through NEIGHBORHOODS.
Rock Creek Park is two or three blocks wide and runs for miles through residential neighborhoods on both sides all the way from beyond Bethesda to downtown District of Columbia.
When I was stationed at the National Naval Medical Center in Bethesda, my house was right at boundary of the Medical Center and one block away from Rock Creek Park.
The question is not whether a highway crossing Rock Creek Park will go through a neighborhood or not.
It WILL go through a neighborhood. That is why it is called an URBAN park.
The only question is whether it will go through Fred's neighborhood or Tom's neighborhood with either Fred or Tom whining about how the route was chosen to advance "environmentalism" while ignoring people.
IIRC, a lot of the designated route for the ICC was left undeveloped in anticipation of the highway being built. It is entirely possible that the portion of the route that was moved went through one of these undeveloped areas.