Woody Guthrie’s famous 1940 song ‘This land is your land, this land is my land’ declared America to be for everyone: ‘this land was made for you and me’. Maps can help persuade us that a nation, empire, or city is ‘your land and my land’, that is, that we have a shared, territorially based, identity (for good or ill). But maps can also do the opposite. In a rarely sung political verse of his song, Guthrie protested that there ‘Was a high wall there that tried to stop me / A sign was painted said: Private Property’. Maps often help individuals stake a claim to property, making some of it ‘my land and not your land’. We explore how and to what effect maps make land your land and/or my land.