Just a heads up to people that AMEX now does travel insurance that includes Potholing in itsadventure travel insurance for Medical and repatriation only (no personal injury compensation). You can also get multi trip annual cover up to 120days per trip if you are over 30. It doesn't cover cave diving, canyonong or solo caving (although its advertising says it does cover cave diving- I've written a letter of complaint about that!)