Did you know Washington DC was originally designed to have large avenues?
The L’Enfant plan was designed to have green areas or buffers. That’s why it is common in DC for folks’ front and side lawns to be on city land.
It’s called “Public Parking”, a funny name but nothing to do with cars.
So, the adjacent property owners need to maintain the property, get to enjoy it and don’t have to pay taxes on it.