Galveston Causeway, Railway bridge in Galveston, US.

The Galveston Causeway is a set of causeways across Galveston Bay and the Gulf Intracoastal Waterway. Two concrete spans carry the northbound and southbound lanes of Interstate 45, while the original 1912 route is restricted to rail traffic. The rail crossing includes a vertical-lift drawbridge that replaced a bascule span in 2012, widening the navigation channel to about 300 feet (91 m).

The original bridge was completed in 1912 by the Penn Bridge Company and initially served both trains and cars. In 1939, a separate vehicle route opened, changing how the bridge was used.

The causeway was re-dedicated on 25 October 2016 in honour of George Mitchell and his wife Cynthia Woods-Mitchell, recognising their contributions to Galveston Island and the city. The original 1912 route, now used only by trains, was listed on the National Register of Historic Places in 1976.

The causeway is the main road access to Galveston Island; the second access is the Bolivar Ferry. The rail causeway's vertical-lift span, installed in 2012, widened the navigation channel to about 300 feet (91 m). The original 1912 route is listed on the National Register of Historic Places.

The 1987 bascule span pivoted from the island side rather than the mainland side as the original did, and its passage was only 105 feet (32 m) wide. The U.S. Coast Guard declared it a hazard to navigation in 2001. The 2012 vertical-lift replacement widened the channel to about 300 feet (91 m), and the old bridge was sold to Sonoma–Marin Area Rail Transit for reuse over the Petaluma River in Petaluma, California.