Galveston Causeway in the context of "Interstate 45"

Interstate 45 (I-45) is a major Interstate Highway located entirely within the U.S. state of Texas. While most primary Interstate routes which have numbers ending in "5" are cross-country north–south routes, I-45 is comparatively short, with the entire route located within Texas. Additionally, it has the shortest length of all the primary Interstates divisible by 5, and is the only Interstate Highway of such. It connects the cities of Dallas and Houston, continuing southeast from Houston to Galveston over the Galveston Causeway to the Gulf of Mexico.

I-45 replaced U.S. Highway 75 (US 75) over its entire length, although portions of US 75 remained parallel to I-45 until its elimination south of Downtown Dallas in 1987. At the south end of I-45, State Highway 87 (SH 87, formerly part of US 75) continues into downtown Galveston. The north end is at I-30 in Downtown Dallas, where US 75 used the Good-Latimer Expressway. A short continuation, known by traffic reporters as the I-45 overhead, signed as part of US 75 and also part of unsigned I-345, continues north to the merge with the current end of US 75. Traffic can use Spur 366 (better known locally as the Woodall Rodgers Freeway) to connect to I-35E at the north end of I-345.

Galveston Island (/ˈɡælvɪstən/ GAL-vis-tən) is a barrier island on the Texas Gulf Coast in the United States, about 50 miles (80.5 km) southeast of Houston. The entire island, with the exception of Jamaica Beach, is within the city limits of the City of Galveston in Galveston County.

The island is about 27 miles (43.5 km) long and no more than 3 miles (4.8 km) wide at its widest point. The island is oriented generally northeast-southwest, with the Gulf of Mexico on the east and south, West Bay on the west, and Galveston Bay on the north. The island's main access point from the mainland is Interstate Highway 45 which crosses the Galveston Causeway that crosses West Bay on the northeast side of the island.