What is the primary characteristic of cobblestones?

Cobblestones are primarily characterized by their more rounded shape. This distinctive feature is what differentiates them from other types of stones or pavers. Traditionally, cobblestones were shaped as rounded or oval stones, often sourced from riverbeds, which naturally led to their smooth and curved edges. This shape not only contributed to their aesthetic appeal but also made them effective for creating durable, stable surfaces for roads and pathways in historic and modern contexts.

The rounded shape of cobblestones allows for better interlocking when laid down, which can create a more solid surface despite the natural variations in size and shape. This characteristic also plays a role in the inherent drainage capability of cobblestoned areas, as the gaps between stones can help water flow through rather than pooling on the surface.

In contrast, other options do not accurately represent cobblestones. For instance, flat, square-shaped stones wouldn't provide the same interlocking mechanism or historical context of use found with rounded cobblestones. Additionally, cobblestones are not made of metal, nor are they typically used for roofing; their traditional uses focus more on ground surfaces and paths rather than structural elements like roofing materials.