A modular roundabout or traffic calming system with interlocking connectors and a method of installation utilize a plurality of boards arranged in a pattern on a ground surface at an intersection of vehicle roadways, the pattern including one or both of a central island and a splitter island. At least some of the boards forming a perimeter of the pattern are affixed to the ground surface. At least some of the boards forming interior boards are interconnected at adjacent edges with connectors. The connectors can include a hinge joint so that the interconnected boards can be folded or rolled. A kit for a modular roundabout or traffic calming system is also provided.