The present invention relates to an area suitable for equestrian use. The area comprises an upper, equestrian surface layer, and a sub-surface support layer which includes a plurality of laterally arranged load bearing structural modules. Each module comprises a top wall and a bottom wall spaced therefrom by one or more supporting elements so as to define an interior volume between the top and bottom walls, and is provided with at least one aperture to permit the flow of water into and out of the volume. There is a system for retaining water within at least some modules in the sub-surface support layer. A water permeable layer that is impermeable to solid particles of the upper, equestrian surface layer is provided between the structural modules and the equestrian surface layer. A wicking system is in fluid communication with the interior volumes of at least some of the modules and have portions extending upwardly to transfer water to the upper, equestrian surface layer from the sub-surface support layer.