There are some 500 brochs scattered across Scotland, especially across the north and west of the country. Built in the last couple of centuries BC and the first couple of centuries AD they combine features of fort, fortified house, and status symbol, and could easily have served different purposes in different places and at different times. Of all Scotland's brochs one quite literally stands supreme: Mousa Broch rises to 13m high and is both magnificent and awe inspiring.

The broch stands on the now uninhabited island of Mousa, a mile or so off the east coast of Shetland's Mainland. Access is by the passenger ferry Solan IV operated by Mousa Boat Trips from Sandwick, some 15 miles south of Lerwick.

The ferry lands at the jetty in the inlet of West Ham, close to the croft from which the RSPB operates Mousa as a bird sanctuary. The island itself is fascinating for those with an interest in birds, or wanting to see seals basking.

But most visitors find Mousa Broch an irresistible draw. To get there you follow a track above the shore of the island for a little over half a mile. The broch comes into view fairly quickly and from there your attention is focused on a structure that just keeps on getting bigger as you approach.

Standing above a rocky shoreline, Mousa was one of a pair of brochs built to stand guard over Mousa Sound. The other is at Burraland on the Mainland on the opposite side of the sound. It is far less well preserved than Mousa.