Build that fence!
Even with the fence built for 20 miles, is is simply a longer hike out to where the barrier to crossing may be a little less formidable. A hike through arid lands that may have rattlesnakes and no refreshment stops, to be sure, but only a momentary pause for somebody who has already traveled hundreds or even thousands of miles, much of it on foot.
And there is always the option of burrowing beneath. Got to be careful about that emergence point, however.
Even with the fence built for 20 miles, is is simply a longer hike out to where the barrier to crossing may be a little less formidable. A hike through arid lands that may have rattlesnakes and no refreshment stops, to be sure, but only a momentary pause for somebody who has already traveled hundreds or even thousands of miles, much of it on foot.
And there is always the option of burrowing beneath. Got to be careful about that emergence point, however.