Before you do any tombstones rubbings, be sure that the stones are in good enough condition that they won't be damaged. Also check first with the sexton or owner of the cemetery for permission to do rubbings. Never go alone to visit a cemetery. It simply is not safe these days. And always tell someone else where you are going and when you expect to return.
Cemeteries located in remote rural areas, as well as in some urban locations, can be dangerous.
If so, check with it first. Possibly maps are available to help you locate your ancestors' graves. Even if you find tombstones for your ancestors, cemetery records may provide additional genealogical material. When visiting older cemeteries, especially, wear clothing that will protect you from poison ivy, briars, insects and snakes. Long pants, long-sleeve shirts and blouses, good sturdy shoes, and a hat are a must.