Yeah, good question. Another thing to consider here is if instead of putting skyscrapers into Central Park, what would happen if it was instead paved over into

Yeah, good question. Another thing to consider here is if instead of putting skyscrapers into Central Park, what would happen if it was instead paved over into a single massive parking lot? I think one way to handle this is to treat each 'scope'(local, state, federal) of government as its own land value tax, and your taxes would go to your local community, but a piece of which would then need to pay the state tax, etc... It would be in the interests of NYC to use their land to the best use that they determine. If they choose poorly and paved over Central Park, this would meaningfully impact their finances. And what of the privately owned Bryant Park, would they need to pay the Land Value Tax despite the fact that they are just as positive externality driving as Central Park? Grand Central Station was another case of this, where the city disallowed the company that owned it to knock it down and build a skyscraper, as renting out the skyscraper would earn the company more money. Georgists care very deeply about tracking the capturing of positive externalities, but this is the opposite. This is attempting to value the release of positive externalities. I don't have a perfect answer for this, but it's clear there are 'privately-owned' places that act as publicly-owned, and thus if we exempt from taxes public, they deserve to as well. I don't like exemption, - it will surely breed corruption - but I see no real way to find out what that value really is.