I’m uncertain how locked into the laws of physics Zombies are, but I’ve always thought the best strategy would be to head toward any sufficiently elevated area. My reasoning is that zombies would follow the path of least resistance, and since it takes more effort to climb than descend, eventually most zombies would wind up in the lowlands. That’s assuming, of course, that it requires any energy at all for zombies to move.
There’s a cracked.com article on the best weapon against zombies being a light saber. With it, you never run out of bullets, never needs sharpening, cauterizes what you kill to minimize mess, can use it to cut off infected limbs without people bleeding to death.