I would suggest that there are actually a lot of these places to go and land. Unfortunately unless you own your own aircraft though, you won't be going to them. The ones on private property are generally owned by careful pilots with an alternate who won't give just anybody permission. The ones on public land (here in Aus) are a permission risk where it's way easier to seek forgiveness than obtain permission. You won't hire an aircraft to go to any of them unless you keep your destination a secret or the owner knows the strip and your ability. If your caught you will suddenly find that you can no longer hire :-) If you damage, someone may well want a reimbursement.
I have a criteria for visiting any of these places and it's something like this:
Can I drive or walk easily to the location? Iif so what's the point?
Is there something to do when I am there, ie a reason for visiting. camping, fishing, exploring, swimming? If not, what's the point?
Am I unduly risking my aircraft? Speaks for itself.
I would suggest the following practice: Arrive over the piano keys at at least 100". Touch down EXACTLY on the 500" marker. Keep the centreline exactly between the wheels. Stop without burning out the brakes in "book" distance. Get the ability to do it in any weather conditions including crosswind to the maximum. Can't do it in a strong crosswind? Not ready for marginal!
If you can do the above 10 out 10 times perhaps youn ready for something slightly more challenging. Not saying you can't do it, you possibly already can! Just saying.