A system for anchoring inflatable structures having a base which, when the structure is inflated, rests on a supporting surface to support the structure, includes at least one water receiving anchoring portion positioned adjacent a side of the base of the structure that rests on the supporting surface and which is secured to and extends from the inflatable structure. The water receiving anchoring portion includes a water receiving section to receive water therein and a shaping section to provide a shape to the water receiving section and to the water receiving anchoring portion to ease filling of the water receiving section with water. The shaping section shapes the water receiving section generally into a cup or bucket like structure so that water can be poured into the water receiving section without the water receiving section being held in such shape by hand or without having to be filled with pressurized water.