Question about Cross of Saint George

First off, newbish to the game so a newbish question. Is a Cross of Saint George similar to a claim stone in that you can walk through it like fallen logs, etc.?
Secondly, its gonna be very difficult to setup the crosses to "get the most out of them with my current setup" without destroying some stuff , can you place a cross, use it to place another cross since you have to be within town borders and then destroy the first cross that allowed you to place the second cross, therefore getting more land for the upkeep?
Secondly, its gonna be very difficult to setup the crosses to "get the most out of them with my current setup" without destroying some stuff , can you place a cross, use it to place another cross since you have to be within town borders and then destroy the first cross that allowed you to place the second cross, therefore getting more land for the upkeep?