An interlocking attaching system comprises a substrate adapter, an accessory adapter and a discrete locking member. The substrate adapter includes a base for affixing to a substrate object and a plurality of spaced apart raised regions disposed along a first longitudinal axis. The raised regions have slots defining a first plurality of passages oriented parallel to the first longitudinal axis and aligned with one another. The accessory adapter includes a base for affixing to an accessory object and a plurality of spaced apart raised regions disposed along a second longitudinal axis. The raised regions have slots defining a second plurality of passages oriented parallel to the second longitudinal axis and aligned with one another. The spacing between the locations of the raised regions of the adapters are dimensioned to position at least one raised region of one of the adapters between at least two raised regions of the other adapter when the adapters are in operational alignment, i.e., with their respective top sides together and with their respective passage aligned. The locking member is removably insertable through the passages on both adapters when the adapters are in operational alignment. Insertion of the locking member through the passages of both adapters when the adapters are in operational alignment interlocks the accessory object to the substrate object, and withdrawal of the locking member from the passages releases the accessory object from the substrate object.