There is something to be said for the UK traipsing laws from time immemorial - because you can explore something other than a million square kilometers of mostly unused land.
that's the point. America has green spaces, UK has country side, terroir if you will.
A green space is a delineated, commoditized destination. Drive there, park there, do your thing, go back. A country-side can be enjoyed through osmosis, even when living in the city.
They're qualitatively different.
Opinions on property rights aside there is no lack of land to explore and enjoy.
Aside from there there are also state parks and forests, though the states define their own terms of use and enjoyment around them.
It's less about delineated activities (which are a number, countable, very modernist), and more the day2day enjoyment of nature, as it bleeds through city life, you don't necessarily seek it out, it just happens (which can't be put into a number, can only be waxed rhapsodically about, very humanist). It's visiting family one town over, leaving your city house and smelling cow shit as you bike there. It's a train commute and seeing the fog roll over centuries year old pastures on the way. It's eating venison in a tavern restaurant in fall, and was shot by the local hunter's club. It's a date that starts as a forest hike in the afternoon and imperceptibly blends into a pub crawl at night.
I live in a city of a state which is by all accounts rugged and rustic, in close proximity to wilderness, parks, farmland, etc... but there's a clear separation of intent. When I lived in Europe, the enjoyment of nature was more through a surrounding vapor, unconscious.
I'm not saying that one is necessarily worse, but to me the experience is starkly different, and that difference can't be captured in numbers.
It's also a spectrum, location dependent, ymmv, blah blah etc..
To me there has to be the people to give the nature significance. Otherwise it's not so much exploration as it is just a massive camping trip.
FFS, there's a National Park in New York City: Gateway National Recreation Area. At least I hope it's still there: used to go mountain biking there a long time ago.
I've lived in Georgia for most of my 40 years, and most of these parks I had never heard of until we went there. I think almost every single one has been a really good experience. And it's very affordable for my family of 5. We don't have to go far. They're all a little bit different.
I've seen Yosemite, and the Grand Canyon, and other sites of note in the US. They are really neat, and can be worth the trip. But I'm pretty sure at this point that I'll never even see everything that my home state has to offer in my lifetime, so I'm pretty content to stick to reasonable driving distance.
But yes, once a private entity owns the land in the US you'll need permission to do anything.
In the rest of the UK, it's a little more complicated (for now): https://en.wikipedia.org/wiki/Freedom_to_roam#England_and_Wa...
We have an extensive network of public foot paths and bridal ways that private land owners aren’t allowed to block if they go across their land. There are several through sheep fields, cow fields, crop fields and even a couple of stable fields where people keep their horses with a 5 minute walk of my house.
I can't believe this actually needs to be said.
Not really :)
However I had just read this: https://www.bbc.co.uk/news/world-us-canada-68077595
There's a fight going on around "corner cutting" - https://earthjustice.org/experts/tom-delehanty/wyoming-court...
The end result is that you can essentially 'point in a rough direction' and walk however far you want, however not just on any part of the land. A good OS map, analog or digital, helps.