The small town of Alberobello in Italy, displays some remarkable examples of a traditional mortar-less construction called Trulli. These dry stone huts are constructed out of limestone slabs stacked on top of each other to form pyramidal, domed or conical roofs. Despite the lack of mortar, the structure is surprisingly stable. Trulli were constructed using roughly worked limestone boulders collected from neighboring fields. The structural walls are laid directly on the bedrock, after removal of the topsoil when necessary.