Sapine, Castell of
Sapinoie, Sarpenic, Sarpetine, Sarpine, Serpentine
This is where King Lot, in rebellion against Arthur, laid an ambush for Arthur. Arthur learned of the plot in advance and was ready. In the ensuing battle, Gawain captured Lot and forced him to surrender to Arthur.
It might be identical with La Sapinoie.