New to RV,when traveling how do you know what areas to avoid

I camped at a State Park just North of Memphis while in the area for a family situation. One night while driving home from the Elvis Presley Trauma Hospital downtown we ended up in a bad area of town at 11pm.I was low on gas, my error and didn't know where we were at. An officer pulled me over just a short ways from the park as he saw my out of state plate. Thank goodness he stopped me, as we were getting nervous. He told us to follow him and he would get us to the campground entrance safely!