A building unit has a substantially planar base having an outer periphery including multiple mating sides. Each mating side has at least one “S”-connection, which includes at least one outwardly extending male mating section and at least one inwardly extending adjacent female section. On the base, there are multiple cobbles or raised regions separated by false joints. A first portion of the raised regions are positioned on the male mating sections, respectively and extend to positions proximate to the outer periphery of the base. A second portion of the raised regions are positioned adjacent the female mating sections, respectively and are set back from the outer periphery. Each side of one unit can mate with any side of another like unit. The arrangement results in a surface covering that lacks a discernible pattern.