Cooler bag with a detachable liner and liner base

A cooler bag with a detachable liner and a liner base, wherein the detachable liner is waterproof and removably attached to the cooler bag by a plurality of fasteners comprising one of (a) a plurality of +-shaped slits on a plastic strip on a top margin of the detachable liner engaging a plurality of round studs on a plastic strip on a top margin of the cooler bag and (b) a zipper on the top margin of the detachable liner and the top margin of the cooler bag, wherein the liner base is made of a stiff plastic and has a side wall, wherein a small, low-profile arch arises from an edge of a midsection of the liner base and causes an indented edge next to it, wherein the indented edge curves downward creating a space, wherein a strip with hook and loop patches at each end is threaded beneath the detachable liner and through the space and closes itself with the hook and loop patches at each end, and wherein the detachable liner when detached and folded is held in place by the strip.