In central and northern Italy and in Flanders, the rise of towns that were to a degree self-governing stimulated economic growth and created an environment for new types of trade associations. Commercial cities on the shores of the Baltic entered into agreements known as the Hanseatic League, and the Italian Maritime republics such as Venice, Genoa, and Pisa expanded their trade throughout the Mediterranean.[V] Great trading fairs were established and flourished in northern France during the period, allowing Italian and German merchants to trade with each other as well as local merchants. In the late 13th century new land and sea routes to the Far East were pioneered, famously described in The Travels of Marco Polo written by one of the traders, Marco Polo (d. 1324). Besides new trading opportunities, agricultural and technological improvements enabled an increase in crop yields, which in turn allowed the trade networks to expand. Rising trade brought new methods of dealing with money, and gold coinage was again minted in Europe, first in Italy and later in France and other countries. New forms of commercial contracts emerged, allowing risk to be shared among merchants. Accounting methods improved, partly through the use of double-entry bookkeeping; letters of credit also appeared, allowing easy transmission of money.