Question: USCGC Blackthorn sand in a collision at a bridge spanning what Florida city?

Context paragraphs:
Homestead Extension of Florida's Turnpike: The Homestead Extension of Florida's Turnpike (HEFT), designated as State Road 821 (SR 821) and the Ronald Reagan Turnpike, is the southern extension of Florida's Turnpike, a toll road in Florida operated by Florida's Turnpike Enterprise (FTE).  Spanning approximately 48 mi along a north-south axis, it supplements the 265 mi "mainline" (designated as SR 91) to form the complete 309 mi turnpike.  The extension begins at its southern terminus at US Highway 1 (US 1) in Florida City, and transitions into the SR 91 mainline in Miramar at its northern end.  Despite their designations as different state roads, the mainline and the extension are continuous in their exit numbering.

Bridge in Bangor Borough: Bridge in Bangor Borough is a historic concrete arch bridge spanning Martins Creek at Bangor, Northampton County, Pennsylvania.  It was built in 1915, and is a small, single arched bridge spanning 45 feet.  It features molded ornamental designs on the spandrel walls and abutments.

Upper Bay Bridge: The Upper Bay Bridge, or the Lehigh Valley Railroad Bridge, is a vertical lift bridge spanning the Newark Bay in northeastern New Jersey.  It is used by CSX Transportation travelling through the North Jersey Shared Assets Area of the United States rail network along the National Docks Secondary line.  The bridge is just north and parallel to the New Jersey Turnpike's Newark Bay Bridge.  A notable train using the bridge is the Juice Train, which originates in Florida.

Florida City, Florida: Florida City is a city in Miami-Dade County, Florida, United States and is the southernmost municipality in the South Florida metropolitan area.  Florida City is primarily a Miami suburb and a major agricultural area.

Varapuzha Bridge: The Varapuzha bridge on NH 17 is a cantilever bridge spanning the Periyar river between Varappuzha(Mannamthuruttu to Cheranallur)(Nearest Varapuzha Historical Island) and Cheranallur.  Varapuzha Bridge is the first bridge in Kerala to be constructed using Balanced Cantilever technique(120m span) and also the first bridge in Kerala where Caisson floating technique was adopted.  The construction of the bridge won the National award for the Most Outstanding Bridge(1999) of Indian Institution of Bridge Engineers On 16 January 2001, Varapuzha Bridge was opened to traffic.  This bridge reduces the distance between Malabar and Kochi.

Betsy Ross Bridge: The Betsy Ross Bridge, also known as the Ross Memorial Bridge is a continuous steel truss bridge spanning the Delaware River from the City of Philadelphia in Pennsylvania to Pennsauken, New Jersey.  Built from 1969 to 1974, and opened in April 1976, during the American Bicentennial Year, it was originally planned to be named as the "Delair Bridge", after a paralleling vertical lift bridge owned by Pennsylvania Railroad (which is now used by Conrail and New Jersey Transit's Atlantic City Line), but was instead later named for Betsy Ross, a Philadelphia seamstress and reputed creator of the first American flag in 1776, making it the first automotive bridge named for a woman in America and the second bridge overall (after Iowa's Boone High Bridge was renamed the Kate Shelley High Bridge in 1912).

Sunshine Skyway Bridge: The Bob Graham Sunshine Skyway Bridge, known to locals as the Sunshine Skyway Bridge or more casually the Skyway, is a bridge spanning Tampa Bay, Florida, with a cable-stayed main span, and a total length of 21,877 ft .  It is part of Interstate 275 (I-275) and U.S. Route 19 (US 19), connecting St. Petersburg in Pinellas County and Terra Ceia in Manatee County, Florida, passing through the waters of Pinellas County, Hillsborough County and Manatee County, Florida.  Construction of the current bridge began in 1982, and the completed bridge was dedicated on February 7, 1987.  The new bridge cost $244 million to build, and was opened to traffic on April 20, 1987.  It replaced an older bridge constructed in 1954, which was partly destroyed in a collision in 1980.

Florida's Turnpike: Florida's Turnpike, designated as State Road 91 (SR 91) and the Ronald Reagan Turnpike, is a toll road in Florida, maintained by Florida's Turnpike Enterprise (FTE).  Spanning approximately 309 mi along a north–south axis, the turnpike is in two sections.  The SR 91 mainline runs roughly 265 mi , from its southern terminus at an interchange with Interstate 95 (I-95) in Miami Gardens to an interchange with I-75 in Wildwood at its northern terminus.  The Homestead Extension of Florida's Turnpike (abbreviated HEFT and designated as SR 821) continues from the southern end of the mainline for another 48 mi to US Highway 1 (US 1) in Florida City.

Gandy Bridge: Gandy Bridge is the southernmost bridge spanning Old Tampa Bay from St. Petersburg, Florida to Tampa, Florida.  The original 1924 span was dismantled in 1975.  The second bridge, constructed in 1956 was used for vehicular traffic until 1997, when it was converted to recreational use by non-motorized traffic.  It became known as the Friendship Trail Bridge and was demolished in 2016, after closing in 2008 due to hazardous conditions and several failed efforts to preserve the span.  The third (1975) and fourth (1997) spans of the Gandy Bridge are currently being used for vehicle traffic.

USCGC Blackthorn (WLB-391): USCGC "Blackthorn" (WLB-391) was a 180 ft seagoing buoy tender (WLB) which sank in 1980 in a collision near the Tampa Bay Sunshine Skyway Bridge, resulting in 23 crew member fatalities.

Supporting paragraphs: USCGC Blackthorn (WLB-391) Sunshine Skyway Bridge
Answer: Tampa Bay