would be good at any of their castles across Europe, allowing movement of money without the usual risk of robbery while traveling. Discounting of interest A sensible manner of discounting interest to the depositors against what could be earned by employing their money in the trade of the bench soon developed; in short, selling an "interest" to them in a specific trade, thus overcoming the usury objection. Once again this merely developed what was an ancient method of financing long-distance transport of goods. Medieval trade fairs, such as the one in Hamburg, contributed to the growth of banking in a curious way: moneychangers issued documents redeemable at other fairs, in exchange for hard currency. These documents could be cashed at another fair in a different country or at a future fair in the same location. If redeemable at a future date, they would often be discounted by an amount comparable to a rate of interest. Eventually, these documents evolved into bills of exchange, which could be redeemed at any office of the issuing banker. These bills made it possible to transfer large sums of money without the complications of hauling large chests of gold and hiring armed guards to protect the gold from thieves. Italian bankers The Republic of Venice, sometimes mistakenly credited with establishing a Bank of Venice in the 12th century, did not formally create a public bank until 1587. However in the 13th and 14th centuries its Grain Office did a banking business that included both deposits and lending. The Republic's system of transferable public debt has also been identified as an important contribution to the development of banking. In the middle of the 13th century, groups of Christians, particularly the French Cahorsins and Italian Lombards, invented legal loopholes to get around the ban on Christian usury; for example, one method of effecting a loan with interest was to offer money without interest, but also require that the loan be insured against possible loss or injury, and/or delays in repayment (see contractum trinius). The Christians utilizing these legal loopholes became known as the pope's usurers, and reduced the importance of the Jews to European monarchs. Later in the Middle Ages, a distinction evolved between things that were consumable (such as food and fuel) and those that were not, with usury permitted on loans that involved the latter. The most powerful banking families came from Florence, including the