50 free Dry Tortugas National Park trivia questions with answers — geography quiz, new questions added Aug 2026.
This Dry Tortugas National Park trivia quiz covers the tiny coral islands 68 miles west of Key West that hold Fort Jefferson, the largest brick structure in the Americas. Questions cover the fort itself (16 million bricks, 243 guns never fired, cisterns that failed), the prisoners including Dr Samuel Mudd, the lighthouses on Garden and Loggerhead keys, and the birds, reefs and shipwrecks of a park that is more than 99 percent water. History runs from Ponce de León's 160 turtles in 1513 through the wreck of HMS Tyger, enslaved labourers building the fort, the yellow fever epidemic of 1867, the Navy coaling station where USS Maine loaded before Havana, the Carnegie marine laboratory, Franklin Roosevelt's 1935 monument, the 1992 park, the Atocha treasure and the Key West flotilla that tried to reopen the park during the 1995 government shutdown. Questions run from easy to expert with the difficulty shown on each one. Every answer was checked against a reference page and each question carries its citation. If you enjoy this one, try our Everglades and Biscayne quizzes next.
30 of 50 questions with answers and explanations. Play the quiz
Q 01The Dry Tortugas lie in which body of water, about 68 miles west of Key West?
Gulf of Mexico
The islands are the westernmost and most isolated of the Florida Keys, reachable only by boat or seaplane.
Q 02What is the centerpiece of the park?
Fort Jefferson, a huge unfinished coastal fortress
It is the largest brick masonry structure in the Western Hemisphere and among US forts only Fort Monroe and Fort Adams are bigger.
Q 03Roughly how many bricks went into Fort Jefferson?
More than 16 million
It covers 16 acres of Garden Key; among US forts only Fort Monroe and Fort Adams are larger.
Q 04Who gave the islands the name 'Tortugas' after visiting in June 1513?
Juan Ponce de León
His men caught 160 sea turtles there; it is the second-oldest surviving European place-name in the United States.
Q 05Why are the islands called 'Dry'?
They have no surface fresh water
That lack of water is why the fort was built with an elaborate rain-cistern system that mostly failed.
Q 06What share of the park's area is water?
More than 99 percent
The seven or so keys total only about 144 acres of land, and their number changes as storms and tides expose or drown sandbars.
Q 07What is the highest natural elevation anywhere in the Dry Tortugas, on Loggerhead Key?
10 feet
Loggerhead is the largest key at about 64 acres and carries the 151-foot lighthouse; most of the other keys stand barely three feet above the sea.
Q 08How big was Garden Key, the fort's island, before construction began?
About 8 acres
The fort now covers 16 acres and the key about 42; the primitive campground sits just south of the walls.
Q 09Bush Key was formerly called Hog Island. Why?
Hogs were raised there for fresh meat
It is now a huge rookery, closed from February to September for nesting terns and noddies.
Q 10How did the small key northeast of Fort Jefferson earn its present, medical-sounding name?
A hospital for the prison inmates stood there
It was earlier called Middle Key or Sand Key and covers barely an acre; Middle Key itself vanishes for weeks or months at a time.
Q 11In which year did construction of Fort Jefferson begin?
1846
Plans by Lt Montgomery Meigs, based on a Joseph Totten design, were approved that November; the work was only half done by 1860 and never finished.
Q 12Who did most of the labour building Fort Jefferson before 1863?
Enslaved Black people hired from their owners
About 17 percent of Key West's enslaved population was leased to the Army engineers between 1847 and 1860; the practice ended after the Emancipation Proclamation.
Q 13How many sides does Fort Jefferson have?
Six
Two curtain walls measure 325 feet and four measure 477 feet; each of two casemate tiers held 150 guns with 150 more on top.
Q 21Which Black regiment was stationed at Fort Jefferson at the end of the Civil War?
The 82nd US Colored Infantry
Made up of soldiers from Louisiana, it relieved a New York regiment in September 1865, the day Mudd tried to stow away.
Q 22Which US Navy warship took on coal at the Dry Tortugas in 1898 before its fateful voyage to Havana?
USS Maine
The fleet gathered there for the Spanish–American War; the Navy had run a coaling station on the key since the 1880s.
Q 23Who ran a marine biology laboratory on Loggerhead Key from 1903 to 1939?
Carnegie Institution of Washington
Q 14How many times were Fort Jefferson's big guns fired in anger?
Not once
By 1872 there were 243 large-calibre guns including six 15-inch Rodmans on the top tier, none ever used.
Q 15What went wrong with the fort's ingenious system of cisterns hidden inside its walls?
Salts leached from the sand filters, spoiling the water
Only the runoff stored under the parade ground stayed fresh; two steam condensers distilled 7,000 gallons of seawater a day during the Civil War.
Q 16Which doctor, jailed at Fort Jefferson 1865–69, had set John Wilkes Booth's broken leg?
Samuel Mudd
He arrived with three other Lincoln conspirators in July 1865, tried to stow away on a transport that September and was thrown into the 'dungeon'.
Q 17What was written over the door of the fort's dungeon where Mudd was held after his escape attempt?
'Whoso entereth here leaveth all hope behind'
The line is adapted from Canto III of Dante's Inferno.
Q 18What did Dr Mudd do at the fort in 1867 that helped earn his pardon?
Treated patients during a yellow fever epidemic
The outbreak killed fellow conspirator Michael O'Laughlen and the post surgeon; the president pardoned Mudd in 1869.
Q 19Which president pardoned the doctor in 1869?
Andrew Johnson
A military commission had sentenced him to life, escaping execution by a single vote; his conviction itself was never overturned.
Q 20Which 'Chicago Conspiracy' leader, imprisoned at the fort, supposedly drowned escaping by boat?
George St. Leger Grenfell
The Englishman arrived in October 1865; Lincoln had earlier substituted Dry Tortugas imprisonment for execution for convicted deserters.
It was called the best-equipped tropical marine station in the world; its research vessel Anton Dohrn went to Woods Hole when it closed.
Q 24Which president proclaimed Fort Jefferson National Monument on 4 January 1935?
Franklin D. Roosevelt
He used the Antiquities Act; the WPA then restored the crumbling fort, and Congress made it Dry Tortugas National Park in the 1990s.
Q 25In which year did the monument become Dry Tortugas National Park?
1992
It shares a superintendent with Everglades National Park and is part of the UNESCO Everglades & Dry Tortugas Biosphere Reserve.
Q 26During the 1995–96 government shutdown, Key West residents did what?
Sent a flotilla under the Conch Republic flag to reopen the park
They had raised money to keep the park open but nobody would take it; officials who tried to enter the fort were cited, and the case was dropped in court.
Q 27Who found the 1622 wreck of the galleon Nuestra Señora de Atocha near the Dry Tortugas in 1985?
Mel Fisher
The 'Atocha Motherlode' was worth about $450 million: 40 tons of gold and silver, 114,000 pieces of eight, emeralds and 1,000 silver ingots.
Q 28Which Royal Navy ship wrecked in the Dry Tortugas in 1742, stranding its crew on Garden Key?
HMS Tyger
The castaways fought off a Spanish sloop before sailing to Jamaica in several small boats.
Q 29How many bird species are on the park's official list?
299
Only eight nest there regularly, but in April dozens of migrants can pass through in a day and land in the fort's parade ground.
Q 30The park has the only nesting colonies in the contiguous US of which seabird?
Sooty tern
Brown noddies, magnificent frigatebirds and masked boobies also breed nowhere else in the lower 48; Bush Key hosts the huge tern rookery.