Cropped image of the Blackhouse Museum, Arnol, Isle of Lewis, eliminating some foreground to provide a better balance to the picture. Picture taken on the 17th May 2010 and sharpened in Photoshop along with minimal adjustments to shadows and highlights. Although the Lewis blackhouses have a look of real antiquity most of the upstanding ruins were built less than 150 years ago. The blackhouses on the Isle of Lewis have roofs thatched with cereal straw over turf and thick, stone-lined walls with an earthen core. Roof timbers rise from the inner face of the walls providing a characteristic ledge at the wall head (tobhta). This gives access to the roof for thatching. Both the animals and occupants shared the same door, living at different ends of the same space. Several long ranges, or rooms, were usually built alongside each other, each one having its own ridgeline giving them the very distinctive look of the Lewis blackhouse. The Lewis examples have clearly been modified to survive in the tough environment of the Outer Hebrides. Low rounded roofs, elaborately roped were developed to resist the strong Atlantic winds and thick walls to provide insulation and to support the sideways forces of the short driftwood roof timbers.