The tree isles consist of Corten steel sections with a Rough&Ready sitting edge. The beams are positioned radially, offering a natural anti-skate solution. The unique tree isles are completely stand-alone on the concrete deck or are embedded in the ground. The construction does not require separate foundation. The depth below ground level depends on the particular project in question and is determined by the height of the ground level construction. The standard depth is 15 cm - 6”. The continuous Rough&Ready border seat is beautifully integrated with the Corten steel structure. By using the patented Streetlock® fix-and-replace System, the beams can be easily replaced. Ideal in the event of damage!.