A cellular paving grid, comprising: (i) a plurality of open cell structures each comprising (a) a top edge defining a top open area, (b) a bottom surface comprising at least one bottom opening, and (c) at least one side-wall extending from the top edge to the bottom surface; (ii) a plurality of first connection members that interconnect the plurality of open cell structures; (iii) a plurality of secondary openings defined by the plurality of open cell structures and the plurality of first connection members; (iv) at least a first external row of the plurality of open cell structures comprising first external male open cell structures; and (v) at least a second external row of the plurality of open cell structures comprising external female open cell structures; wherein at least two adjacent external female open cell structures are connected via a first retaining-connection member configured to support a connection member interconnecting complementary external male open cell structures from a second of such a cellular paving grid; wherein the external female open cell structures are configured to receive a complementary external male open cell structure from the second cellular paving grid, and characterised in that the at least two adjacent external female open cell structures comprise open slots that extend from respective bottom sections of the at least one side walls of the at least two adjacent external female open cell structures and terminate at respective intermediate positions along the respective at least one side-walls of the at least two adjacent external female open cell structures, the open slots being configured for receiving the connection members from the second cellular paving grid, and wherein the first retaining-connection member comprises (a) a rib-portion extending in a first direction and connecting the at least two adjacent external female open cell structures, and (b) a retaining-portion extending in a second direction and projection outwardly with respect to the first direction; wherein the second direction is substantially perpendicular to the first direction and the retaining-portion includes a top surface that is proximate to the open slots. (i) a plurality of open cell structures each comprising (a) a top edge defining a top open area, (b) a bottom surface comprising at least one bottom opening, and (c) at least one side-wall extending from the top edge to the bottom surface; (ii) a plurality of first connection members that interconnect the plurality of open cell structures; (iii) a plurality of secondary openings defined by the plurality of open cell structures and the plurality of first connection members; (iv) at least a first external row of the plurality of open cell structures comprising first external male open cell structures; and (v) at least a second external row of the plurality of open cell structures comprising external female open cell structures; wherein at least two adjacent external female open cell structures are connected via a first retaining-connection member configured to support a connection member interconnecting complementary external male open cell structures from a second of such a cellular paving grid; wherein the external female open cell structures are configured to receive a complementary external male open cell structure from the second cellular paving grid, and characterised in that the at least two adjacent external female open cell structures comprise open slots that extend from respective bottom sections of the at least one side walls of the at least two adjacent external female open cell structures and terminate at respective intermediate positions along the respective at least one side-walls of the at least two adjacent external female open cell structures, the open slots being configured for receiving the connection members from the second cellular paving grid, and wherein the first retaining-connection member comprises (a) a rib-portion extending in a first direction and connecting the at least two adjacent external female open cell structures, and (b) a retaining-portion extending in a second direction and projection outwardly with respect to the first direction; wherein the second direction is substantially perpendicular to the first direction and the retaining-portion includes a top surface that is proximate to the open slots.