The Mongols had a strong history of supporting merchants and trade. Genghis Khan had encouraged foreign merchants early in his career, even before uniting the Mongols. Merchants provided him with information about neighboring cultures, served as diplomats and official traders for the Mongols, and were essential for many needed goods, since the Mongols produced little of their own. Mongols sometimes provided capital for merchants, and sent them far afield, in an "ortoq" (merchant partner) arrangement. As the Empire grew, any merchants or ambassadors with proper documentation and authorization, received protection and sanctuary as they traveled through Mongol realms. Well-traveled and relatively well-maintained roads linked lands from the Mediterranean basin to China, and greatly increasing overland trade, and resulting in some dramatic stories of those who traveled what became known as the Silk Road. One of the best-known travelers from West to East was Marco Polo, and a comparable journey from East to West was that of the Chinese Mongol monk Rabban Bar Sauma, who traveled from his home of Khanbaliq (Beijing) as far as Europe. Missionaries such as William of Rubruck also traveled to the Mongol court, on missions of conversion, or as papal envoys, carrying correspondence between the Pope and the Mongols as attempts were made to form a Franco-Mongol alliance. It was rare though for anyone to travel the entire length of the Silk Road. Instead, traders moved products much like a bucket brigade, with luxury goods being traded from one middleman to another, from China to the West, and resulting in extravagant prices for the trade goods.