Interior of the Broch of Mousa on Mousa Island, Scotland

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Interior of the Broch of Mousa on Mousa Island, Scotland

At about 43 feet tall, the Broch of Mousa is shorter than the other brochs scattered across Scotland, but still impressive for such an ancient structure in this forbidding landscape. Archaeologists and historians aren’t sure if these Iron Age stone towers were used for defense, farming, or habitation. The Mousa broch, like the others, has no roof. It has a single entrance and is a dry-stone construct—no mortar was used to hold it together. The broch’s sturdy construction and distant location in the Shetland Islands are likely why it’s still standing centuries later.