A retaining wall is a structure that holds or retains soil behind it. There are many types of materials that can be used to create retaining walls like concrete blocks, poured concrete, treated timbers, rocks or boulders. Some are easy to use, others have a shorter lifespan, but all can retain soil.
Over the years many different retaining wall materials have helped to alter the landscape in which we live. Common retaining wall products include railroad ties or treated timbers as well as wall stones, natural stones, bricks, & concrete block.
While wood is often an inexpensive and simple choice for a retaining wall, its short lifespan makes it a relatively poor choice. As the wood decomposes, so does your retaining wall and the integrity of your usable space. Stones, rocks or boulders can create beautiful retaining walls, but the installation of these materials can be expensive and labor intensive. Furthermore, maintenance of stone walls can be difficult, because over time or they may erode or become home to rodents & weeds.
Cast-in-place or mortared retaining walls are another options. These walls can be installed with a variety of veneers, bricks, flagstones, etc. which add texture and style. However, these structures are rigid & do not move and flex with climate changes, earthquakes & other natural forces & can be very expensive to build.