There is also a theory that the "Welsh Caves" in DeSoto State Park, northeastern Alabama, were built by Madoc's party, since local native tribes were not known to have ever practised such stonework or excavation as was found on the site.
还有一个学说称阿拉巴马东北的迪索托州立公园（Desoto State Park）的“威尔士洞穴”是马多克的团队所开凿的，因为当地的原住民部落并不被知道曾经进行过如此的石工建筑或者开凿活动，并且当地也找不到那样的遗址。