Salcombe_Cannon_Wreck Salcombe Cannon wrecksite is close to two other designated wrecksites in the Erme Estuary which the South West Maritime Archaeological Group (SWMAG) was licensed to investigate. In 1992 this group described the Salcombe Cannon site as"A cannon site with nothing else visible".In 1994, following seabed changes, other artifacts including gold were revealed and the SWMAG began recording the site.