Outdoor Ethernet Cable and Wireless Router Questions?

Okay so i have two properties on my lot, about 15 yards away from each other. The one with the internet modem is made of stone and is not ample for wireless internet. I want to get the internet in the other place for my 360, therefore it has to have a strong constant connection for online play. So i would like to know if there are like super strong wireless routers out there that would have no problem with the stone walls and distance. If not, then what kind of outdoor Ethernet cables can i use, keep in mind i cant bury anything, the ground is already to hard (winter is coming up). So what would work best and how would i do it? Will they stand up through the cold winter? Suspended across, or lying on the yard? Would pvc pipe help protect it if i just laid it across the yard, just until the ground thaws and i can bury it? any help or insights will be greatly appreciated