Hernando de Soto Bridge

The Hernando de Soto Bridge is a tied-arch bridge carrying Interstate 40 across the Mississippi River between West Memphis, Arkansas, and Memphis, Tennessee. The design is a continuous cantilevered cable-stayed steel through arch, with bedstead endposts. Memphians also call the bridge the "New Bridge", as it is newer than the Memphis & Arkansas Bridge (carrying Interstate 55) downstream, and the "M Bridge", due to its distinctive double-arch shape. It is of similar construction to the Sherman Minton Bridge between Louisville, Kentucky, and New Albany, Indiana (except that it consists of a single level deck).

Preliminary planning for the river crossing began in 1960 as part of Interstate 40 alignment studies for the Memphis - Little Rock corridor, which was constructed in segments between 1963 and 1968. Before the Hernando de Soto Bridge was completed, traffic going across the river was carried across the Mississippi River by the Interstate 55/US Route 64/70/79/61 Memphis & Arkansas Bridge crossing, located 2 miles (3.2 km) southwest.

The two states initially feuded over the cost of paying for the bridge. Tennessee officials believed that both states should equally pay for the bridge, while Arkansas officials wanted Tennessee to shoulder a much larger share of the cost due to Tennessee's larger population. Both states eventually agreed to a compromise where Tennessee funded 60% of the cost and Arkansas the remaining 40%. Both states also initially disagreed on the design of the bridge; the original design called for longer through arches and a lower vertical clearance.

Construction of the Hernando de Soto Bridge began on May 2, 1967. Initially planned for completion in 1971, the project experienced multiple delays. The double-arch bridge was opened to automobile traffic on August 2, 1973. A dedication ceremony for the bridge occurred on August 17, 1973. Initially expected to be only $12 million (equivalent to $82.4 million in 2025), the final price tag was approximately $57 million (equivalent to $306 million in 2025).

The bridge is named for 16th century Spanish explorer Hernando de Soto, who explored this stretch of the Mississippi River and died south of Memphis.

At night, the bridge was illuminated by 200 high-pressure sodium vapor lights along its "M" structure. The bridge was first illuminated on September 5, 1986, after $373,000 of private funds had been raised to fund the cost and installation of the lights. Due to some river traffic having issues with the lights at night reflecting on the water, the city installed a remote switch to toggle the lights on and off briefly while the vessel passes under the bridge. During the 2011 Mississippi River floods, the bridge became dark for about 2 months because the transformers that supply the electricity for the lights were removed to prevent damage to them by flood waters. The bridge was re-lit in a ceremony which occurred on June 21, 2011.

After the debut of the pedestrian/cycling Big River Crossing and accompanying new LED lighting system on the nearby Harahan Bridge in 2016, it was announced that the existing sodium vapor lights along the Hernando de Soto Bridge would be replaced with a new LED lighting display, thus making the Hernando de Soto the second Mississippi River bridge to feature such a display. The new system can be synchronized with the Harahan Bridge and display various color patterns for special occasions or requests. Both displays have been created under an initiative called "Mighty Lights." The $14 million privately funded project was completed in 2018.

On August 23, 2007, an inspector discovered that a bridge pier on the approach bridge west of the river had settled overnight, and the bridge was subsequently closed to perform a precautionary inspection. The bridge was reopened later that day.