Historically, an Icelandic farmer would build a small farmhouse. Then, as his needs grew, he would build an additional farmhouse attached to the first. He might later add a third and even a fourth attached farmhouse.
The Pearl is a landmark building that stands 61 meters above sea level. It serves a a storage place for the geothermal (hot) water high enough to serve 10-story buildings in Reykjavik. It also holds the Saga Museum, the basis of the Icelandic language that serves as the standard for language in Iceland. The Sagas tell the history of ancient Iceland.
Mostly buildings in Iceland are fairly new, less than 20 years old. One exception is the old town area of Reykjavik.