a right turn lane onto the De Renne Avenue frontage road, and a school zone designation following the frontage road right turn to the Interstate's eastern terminus at Montgomery Street. The southbound entrance onto Mildred Street is often closed by concrete barriers, as it's primarily used to directly access Hunter Army Air Field from the Interstate. The entire length of I-516 is included as part of the National Highway System, a system of roadways important to the nation's economy, defense, and mobility. History 1920s to 1960s The road that would eventually be designated as I-516 was established at least as early as 1919 as a segment of SR 21 from the current western terminus of I-516 to an intersection with SR 26. In 1926, US 17/SR 25 were designated along this section of SR 21. Between 1963 and 1966, I-16 was under construction in Savannah, and the majority of what would become I-516, from Augusta Avenue to its current eastern terminus, was being proposed as SR 26 Loop. Later, in 1966, SR 26 Loop was completed (but not to freeway standards) from just east-southeast of what is now the Veterans Parkway exit to La Roche Avenue, with a proposal to extend it northward through Savannah State University. The rest of the proposed route was also under construction at that time. Also, the construction of I-16 continued to proceed. In 1967, the section from I-16 to just east-southeast of what is now the Veterans Parkway exit was still under construction but scheduled to open "Spring '68". I-16 was completed in Savannah at this time. In 1968, the segment of SR 26 Loop from I-16 to just east-southeast of what is now the Veterans Parkway exit was opened (at freeway standards). 1970s to 2000s By 1970, the segment from Augusta Avenue to I-16 was opened (at freeway standards). Later that year, there was a proposal to extend the western terminus a little farther to the west, to meet what is now US 80/SR 25 Connector/SR 26. Between 1977 and 1979, the entirety of SR 26 Loop, with the exception of the segment between Skidaway Road and La Roche Avenue, was redesignated as an extension of SR 21. The Skidaway–La Roche section was removed from the state highway system. Due to this, the proposal to extend SR 26 Loop from La Roche was removed, as well. By March 1980, the freeway portion was