Interstate 275 forms a 60-mile loop west from Interstate 75 through the urban cores of both Tampa and St. Petersburg. A busy route, the freeway winds northward from the Sunshine Skyway through southern Pinellas to the Howard Frankland Bridge across Old Tampa Bay. The freeway turns east toward Downtown Tampa and north along a congested corridor from near Ybor City to North Tampa and Lutz.
Interstate 275 was commissioned in 1973 over the former path of Interstate 75 through both Tampa and St. Petersburg. Construction of I-275 through Tampa initially focused on the stretch between Downtown Tampa and the Howard Franklin Bridge between 1960 and 1964 and from Pasco County southward to Bearss Avenue, which opened in 1961. The east-west portion of the route was designated as Interstate 4 with four overall lanes and an eight foot grassy median.6
Construction of the Downtown Interchange, where I-4 and I-275 currently meet, was completed in 1965. This preceded work to open I-75 southward from Bearss Avenue in 1966. The vigorously opposed stretch of I-75 between Sligh and Floribraska Avenue was completed in December 1967.6
Further south, Interstate 275 spans Old Tampa Bay across the three-mile long Howard Frankland Bridge. The bridge first opened in August 1960 with a single span dumping traffic onto 4th Street North at its west end. Completion of I-75 south into Pinellas aided in the transformation of 4th Street into a busy commercial route. Ensuing commercial interests established along the route delayed construction of I-275 until 1969, when work commenced on an extension south to Roosevelt Boulevard (SR 686) and 58th Avenue North. Subsequent construction extended the freeway south to I-375 in 1978, and I-175 by April of 1980.7
South from Downtown St. Petersburg, construction on I-275 commenced in June 1978. Resistance to the new freeway was less than previously encountered in areas to the north, but opposition from both environmentalists and Eckerd College resulted in some hurdles. Agreed compromises between parties involved were incorporated into the freeway design including landscaping, the installation of sound walls, the rebuilding of a popular marina displaced by the route and the redesign of the Pinellas Bayway/54th Avenue S interchange to reduce to impact to Eckerd College land. Work took I-275 southward to a temporary end point six times from 1978 to 1984. The portion south to 28th Street South opened in January 1981, to 22nd Avenue South in May 1982, and to 54th Avenue South in January 1984.8 The route through to the famed Sunshine Skyway Bridge was opened by June 1985. The cable-stayed bridge was completed in 1987, replacing a cantilever bridge by the same name that partially collapsed in 1980. The four-lane toll bridge totals 4.2 miles over the main shipping channel for both Port Tampa Bay and Port Manatee.
As traffic counts increased, capacity improvement projects were made to Interstate 275 in both Hillsborough and Pinellas Counties. Reconstruction of the freeway took place in Tampa through the 1970s, with expansion to six overall lanes and redesign of the diamond interchange at Memorial Highway (SR 60) into a parclo between 1974-76. The Himes Avenue interchange was first proposed in May 1983 and advertised to enhance access to Tampa Stadium for the 1984 Superbowl. The partial interchange was to be funded by the Tampa Bay Bucs franchise and Westshore mogul Al Austin, who owned a large tract of land near the stadium location. Funding did not acrue in time for the Superbowl, and the interchange was built in late 1984 and paid mostly by the state.6
The Gandy Boulevard interchange with SR 694 was partially completed in 1976. Plans at that time called for Gandy to be built as a full freeway, so elements of the junction with I-275 were tabled until that upgrade came to pass. The cancellation of the Gandy Freeway led to an upgrade at the interchange with I-275 to provide the previously missing movements.7 A second span for the Howard Franklin Bridge across Old Tampa Bay opened in August 1991. The bridge did double duty while crews rehabilitated the 1960 span, ultimately leading to eight overall lanes of capacity.
Modernization of the freeway through both Tampa and St. Petersburg commenced in November 1999 and continues through fall 2016. This includes the total rebuilding of I-275 between the Howard Frankland Bridge and Downtown Interchange with new carriageways and a wide grassy median reserved for potential light rail. Work included the acquisition of several blocks worth of property to the south of I-275 to accommodate the wider footprint.