D. Bridges to Cross

In its most general form, a bridge is a means of connecting two points: a physical way of getting from "here" to "there," providing a route in whose absence the journey would be more difficult if not impossible. A physical bridge is almost always over geographical territory: a river, canyon, or canal. In one sense, the bridge blots out what it crosses (as an observer can't see through the bridge to what lies directly below) but in another sense the bridge accentuates that which it crosses; if the gap did not exist, neither would the bridge, which by connecting the two ends, provides an alternative to what lies beneath. This connective function was acknowledged by Francesco Sansovino, who in his description of Venice specifically stated that bridges were to join islands one to another; and John Evelyn, writing in his diaries, noted that bridges "tack the city together." [1]

As the city grew, means other than boats of getting around the city had to be found. However, for centuries there was no official interest in such routes. Pedestrian routes therefore grew up in a random, haphazard manner, without civic regulation or esthetic values. The most important factors were the necessity to tie together locations spatially separated by water, and a preference for staying as near as possible to the water, which was the main means of transport. [2] Although it appears that there were already traces of some sort of pedestrian traffic from the Rialto area to Cannaregio in the seventh century, it could have been neither extensive nor well-maintained. [3] Nor could it have involved a large choice of routes, for up until the thirteenth century, there were only eleven bridges. [4] The first stone bridges were built in approximately 1170, while the first attempt to span the Grand Canal was a wooden pontoon bridge at the Rialto in 1180. [5]

Medieval and Renaissance bridges in Venice were constructed either from wood or masonry. [6] The choice of materials was ultimately connected with a number of factors, including money and time available, the size of the span to be crossed, the expected load, and various considerations of ceremony or display. There was also an historical factor at work in selection of material: older bridges were more likely to be of wood, although several of the earliest bridges were originally constructed in stone, [7] such as the bridge on the riva [8] south of what is now the Procuratie Nuove. [9] By 1400, masonry bridge building had caught up with timber work, and in fact was probably outpacing it, as more wooden bridges were replaced by stone. [10]

Wooden bridges, in their simplest form, were nothing but wooden planks laid from bank to bank. In order that boat traffic, including standing boatmen, could pass underneath, the planks might be laid at a height of several feet over the canal, supported by pilings or by lashed-together boats. These pilings were generally placed in the middle of the canal if space permitted, but supports might also be set upon the banks. Access to the planks was by steps or ramps; the earliest bridges were ramps, with no steps, facilitating animal and wheeled traffic. [11] New bridges could be constructed in a hurry, and the entire assembly could be taken apart or moved should the need develop. A large-scale example, although one that did not come into play until 1576, was the bridge erected each year for the Redentore festival.

More permanent wooden bridges could take several forms, from simple ramps that met in the middle, still relatively convenient for the transport of wheeled loads or animals, to arched confections involving steps, or even to drawbridges. [12] All such bridges required more sophisticated construction and design techniques, took longer to build, and cost more money. Unlike their flat cousins, they could not be easily disassembled and moved. [13] A temporary wooden bridge carried with it connotations of impermanence; a route relying on such a bridge might be available one day and gone the next, and it would therefore have much in common with the fluid nature of water-borne traffic. A "permanent" wooden bridge--one that was constructed rather than thrown together--was a step toward fixing the route in place, but was still liable to sudden disappearance, usually by fire, although, as in the case of the successive bridges at the Rialto, possibly through wear, tear and collapse. The commitment of resources to the project of building such a bridge was a sign that the route had assumed an importance that required more of an investment than a few planks and some pontoons, hastily cobbled together.

Finally, masonry bridges represented the highest level of commitment to a particular crossing. As of 1300, there were nine stone bridges. Four of these bridges were in densely-settled, high-traffic-locations as compared to six out of their eight wooden counterparts. [14] All of the stone bridges of this era were across rather narrow spans; bridges such as the Ponte Guglie, over the widest spot in the Cannaregio Canal, were of wood. Throughout the next century, at least twenty-five stone bridges were put into place, with some undoubtedly replacing wooden ones. The fifteenth century saw the construction of at least twenty-three masonry bridges, but the major explosion in masonry construction took place during the sixteenth century. By 1581, Francesco Sansovino was able to report that there were over 450 stone bridges. [15]

A masonry bridge required either a narrow span or elaborate design and construction. The Rialto was one of the last wooden bridges to be replaced by stone, a feat not accomplished until 1588-91. [16] Unlike wooden bridges, stone bridges could not simply use pilings as end supports, having to rely on other means to raise them sufficiently high in the middle to permit passage underneath. Usually, this was done by constructing the bridge as an arch. The upper surface of the bridge generally included steps, except for the center section. For masonry bridges, railings or sides were optional; many bridges had neither, although the 19th-century replacement of many stone bridges added a railing to almost all of them, so that the only present-day survivor without a railing is a bridge in the Cannaregio sestiere. Most masonry bridges did not rely on pilings placed in the canals. The only extant exception is the Ponte Tre Arche, built around 1700 over the Cannaregio canal; here the span is probably the widest, except for the Rialto bridge, to be crossed until the post-Napoleonic era.

Venice in the Cinquecento was in the middle of a period of concerted bridge-building. In 1500, Jacopo de'Barbari's map showed 166 bridges, divided equally between wood and stone. Many of these had been built in the previous century; there were 63 bridges documented as of 1400. Therefore, if Sansovino's 1581 claim of 450 bridges is to be believed, in the intervening 80 years almost 300 bridges were built, and a further 80-odd wooden bridges were replaced with stone. These bridges could be built partly because the land-development efforts had shrunk the distances between the islands; canals became straighter and narrower, making them easier to span.

The exact placement of a bridge was the result of a variety of factors. At the time that bridge-building became almost solely a matter of replacement, every island had at least two bridges, and there was at least one bridge to each neighboring island. [17] The earliest bridges were placed at the most convenient spots, which would usually have been the narrowest passages between two islands. Later, placement was dictated by available open space; there are several bridges in which a straight line was not possible, and the bridge had to be placed at an angle to the canal or had to shift direction in midstream. While bridges are indeed the meeting points of the two "systems" of Venetian movement, terrestrial and water-based, they are connected only to the land-based system. Entry to and exit from bridges was strictly to and from streets and footpaths; the connection to the world of the canals was made by stairs that, because of those same space considerations that determined bridge placement, were not necessarily located next to the bridge. Older bridges were more likely to be located in proximity to water stairs.