"As far as I know, there are only three brick goat towers in the world. There's one at the Fairview Winery in South Africa and one in Portugal," says Johnson.

The tower's spiral steps consist of 2 1/2-in. sq., 40-in. long concrete slabs with rerod in them. The steps are cantilevered through a double row of bricks and are about 1 in. apart where they meet the tower, but about 6 in. apart at the ends.

The roof is intentionally steep to keep birds from roosting. It's made out of copper because it's long lasting and, again, birds won't roost on it. He had to use a crane to lift the roof into place.

The roof is supported by wheels that ride on a circular steel rail along the upper edge of the tower wall. "I cut a door into the roof and plan to use a garage door opener to rotate the roof and use it as an observation tower. I might even bring a telescope up there to look at stars," says Johnson.

"People often ask if any goats ever fall off the tower, and I always tell them the answer is no because goats are very sure-footed. Once in a while we do get freezing rain, and then I use a portable torch to melt the ice from the steps."

The concrete floors give structural support to the tower, says Johnson. "About every six months I use a high pressure water hose to blow manure out of each room. It washes out onto the ground, and later I scoop it up and use it for fertilizer on my farm," he notes.

Additional Information - The Goat Tower at Fairview, Paarl

The Goat Tower at Fairview Wine and Cheese farm is a landmark in the Paarl winelands of South Africa . It is the first of four documented structures of this kind. The Goat Tower was built in 1981 by Fairview owner Charles Back and has become the farm's most identifiable symbol and aspect of their brand. Fairview has more than 750 Saanen goats on their farm, the milk from which is used to produce a range of cheeses under the farm's label. A select group of these goats have the privilege of living in the tower.

Other goat towers:

Argentina - The Torre de Cabras at the Fínca el Rocio in the Mendoza province of Argentina was completed in late 2010. The tower was built using the same plans that were drawn up for the tower in Norway. These were provided to Fínca el Rocio by Fairview following a request by the South American farm's owners.

Norway - In 2006 a farmer from Ekeby in Norway approached Fairview owner Charles Back requesting permission to build a replica of Fairview's tower on his farm in Scandinavia. The Paarl tower was measured and photographed, and the replica tower was completed in 2007, with Charles Back travelling to Norway to officially open the tower.