Seawalls are structures built along coastlines to protect land from the effects of waves and erosion. They are typically made of concrete, stone, or other durable materials and serve to absorb and deflect wave energy, helping to prevent flooding and damage to coastal properties. These structures can vary in design and height, depending on the specific needs of the area. Seawalls are often part of broader coastal management strategies that may include other measures like beach nourishment and breakwaters to enhance shoreline stability and protect ecosystems.