Tour guides make their living by showing foreigners local sites. Guides rely on wealthy individuals living fairly nearby, since even relatively small voyages take copious amounts of time under ancient conditions. Most tour guides loiter at busy ports or near city entrances searching for anyone who looks foreign or rich (preferably both) – then they pounce. In many ways guides are like beggars, only they offer some service (albeit often of dubious value) for the money they request.