Los Angeles Crevasse

From TARDIS Index File, the free Doctor Who reference.

The Los Angeles Crevasse was a canyon presumably located on or near the site of the city of Los Angeles in what was once California at some point in Earth's far future. Cassandra O'Brien claimed that her parents were buried there. (DW: The End of the World)

Whether this area still existed after the National Trust reshaped Earth's geography into the "Classic Earth" is unknown.