Well depends on what kind of area you live in. If you live in suburbs you can always find closed off paths on hiking trails or secluded woods in any nearby park.
If you live in a city, theres always blocked off paths where no one will find you. You can also CTB inside a big dumpster no one touches, as it is best for people to not find you.
You can always find secluded cliffs on google maps as well, if you have a license and can get to that location you can jump and nobody will see.