Patent ID: 8448403

Claim:
A system of building blocks, comprising: a plurality of hollow building blocks, each hollow building block comprising: a cavity, an upper surface, a lower surface, and a plurality of sidewalls extending downwardly from a peripheral edge of said upper surface to a peripheral edge of said lower surface; said upper surface comprising a first opening configured to vertically interlock to a second opening on said lower surface of a vertically adjacent hollow building block, wherein said first opening extends upwardly from said upper surface, forming a projecting mouth through which liquid may enter said cavity and wherein said second opening extends upwardly from said lower surface, forming a recessed mouth through which liquid may exit said cavity; said plurality of sidewalls comprising an interlocking projection and an interlocking socket, wherein said interlocking projection is configured to mate with said interlocking socket of a horizontally adjacent hollow building block; and a gutter assembly having a plurality of spouts, each spout configured to vertically interlock to said second opening of a vertically adjacent hollow building block, wherein said gutter assembly comprises a plurality of gutter assembly sections, each gutter assembly section comprising: a bottom surface, a left end, and a right end; said bottom surface comprising at least one of said spouts; said left end comprising an interlocking tongue; and said right end comprising an interlocking groove; wherein said interlocking groove is configured to engage said interlocking tongue of a horizontally adjacent gutter assembly section.