While the Vikings are usually thought of as plundering pirates, their voyages abroad were also for the sake of trade. While their first advances out of Scandinavia into the wider world were in search of Islamic silver, the dirham, they soon expanded trading routes not only into the European continent, but from the North Atlantic all the way to areas around the Caspian Sea. As trade flourished, the Viking world was built on these networks, and their homelands became distribution hubs and then commercial zones.