Sidney Lanier Bridge, Cable-stayed road bridge in Brunswick, United States

The Sidney Lanier Bridge is a cable-stayed road bridge carrying U.S. Route 17 over the Brunswick River. Two H-shaped concrete pylons, each 486 ft (148 m) tall, rise from the deck; 44 stay cables fan down from each side of every pylon, 176 in all, each 0.6 in (15 mm) in diameter and sheathed in high-density polyethylene. The central span measures 1,250 ft (380 m), with two side spans of 625 ft (191 m) each. The concrete deck is about 11 in (280 mm) thick and 79.5 ft (24.2 m) wide, holding four 12 ft (3.7 m) lanes and an 8 ft (2.4 m) shoulder.

After ship collisions with the original lift bridge in 1972 and 1987, the region decided to build this new structure. The construction opened in 2003, allowing larger cargo ships to pass safely beneath the elevated roadway.

The bridge is named for Georgia poet Sidney Lanier, whose poem "The Marshes of Glynn" describes the salt marshes of Glynn County around the crossing. Each year the south side of the span closes to traffic for the Bridge Run sponsored by Southeast Georgia Health System, and runners register to cross it on foot.

The bridge carries four 12 ft (3.7 m) travel lanes of U.S. Route 17 with an 8 ft (2.4 m) shoulder on each side; the deck is about 11 inches (280 mm) thick. It stands immediately south of downtown Brunswick and about 5.4 mi (8.7 km) upstream from the river mouth, with the Jekyll Island causeway beginning near the southern approach.

The bridge's two hollow H-shaped pylons, each 486 ft (148 m) tall, can be entered so inspectors reach the anchor points where the stay cables are grounded. Each of the 176 cables is 0.6 in (15 mm) in diameter and sheathed in high-density polyethylene.