Return to bridge diagram			Arch Longfellow Bridge over Charles River First used during the Roman Empire, this type of bridge dissipates its weight outward along the arches. Abutments support the arches, absorbing the load and preventing the ends of the bridge from spreading out. Each arch can span up to about 500 feet.

			Truss Tobin Bridge over Mystic River Piers rest underneath the bridge deck, but the truss structure provides extra strength needed to fully support the weight of the bridge. Truss bridges typically run from 100 to 1,600 feet between supports.

			Suspension Golden Gate Bridge Vertical cables carry the weight of the bridge up to two or more main cables draped over towers. The main cables transfer the load to giant anchorages in the ground at each end of the bridge. These bridges are best for long spans of up to 7,000 feet.

			Cable-stayed Zakim Bridge Similar to a suspension bridge in that cables support the bridge deck. A cable-stayed bridge does not have massive anchors at the ends, but instead transfers the weight directly to its towers. Cable-stayed bridges are best for medium-length spans of 500 to 2,800 feet.