Artists creatively merge letterboxing design principles into outdoor sculptures by employing techniques that emphasize framing, layering, and spatial storytelling. Letterboxing, traditionally a form of treasure hunting involving hidden containers and logbooks, inspires sculptors to incorporate narrow, elongated forms or enclosed spaces within their works. These elements create a sense of discovery, inviting viewers to engage with the sculpture from specific angles or perspectives.

Materials like corten steel, wood, or stone are often used to craft these pieces, with cutouts or negative spaces mimicking the "letterbox" effect. Some artists even embed hidden compartments or interactive features, echoing the playful nature of letterboxing. By blending this design approach with large-scale public art, sculptors transform urban landscapes into immersive experiences, encouraging exploration and interaction. The result is a unique fusion of functionality and aesthetics, where art becomes a gateway to curiosity and adventure.