St. Petersburg is a city in Pinellas County, Florida, United States. As of the 2013 census estimate, the population was 249,688, making St. Petersburg the 5th most populous city in the state of Florida and the largest city in Florida that is not a county seat (the city of Clearwater is the county seat). St. Petersburg is the second largest city in the Tampa Bay Area, composed of roughly 2.8 million residents, making it the second largest Metropolitan Statistical Area in the state. It is also a popular vacation destination for both American and foreign tourists.The city is often referred to by locals as St. Pete. Neighboring St. Pete Beach formally shortened its name in 1994 after a vote by its residents. St. Petersburg is governed by a mayor and city council.The city is located on a peninsula between Tampa Bay and the Gulf of Mexico. It is connected to mainland Florida to the north; with the city of Tampa to the east by causeways and bridges across Tampa Bay; and to Bradenton in the south by the Sunshine Skyway Bridge (Interstate 275), which traverses the mouth of the bay. It is also served by Interstates 175 and 375, which branch off I-275 into the southern and northern areas of downtown respectively. The Gandy Bridge, conceived by George Gandy and opened in 1924, was the first causeway to be built across Tampa Bay, connecting St. Petersburg and Tampa cities without a circuitous trip around the bay through Oldsmar.