Key West, Florida, honours Queen Elizabeth at Southernmost Point marker

Queen Elizabeth II and Prince Philip visited the Florida Keys in 1991 and toured historic Fort Jefferson in the Dry Tortugas. AP

The Southernmost Point marker in Key West, Florida, a landmark delineating the continental US’ southernmost spot of land, became a memorial to Queen Elizabeth II on Friday when city workers installed a British flag and royal purple banner at the much-photographed site beside the Atlantic Ocean.

The tribute was particularly fitting because the long-reigning monarch, who died on September 8 at age 96, visited the Florida Keys in 1991.

“We do have a connection with the queen; we had the privilege of actually having her visit us,” Key West Mayor Teri Johnston said.

Reagan laughs following a joke by Queen Elizabeth, who commented on the lousy California weather she has experienced since her arrival in the US. Getty Images

Queen Elizabeth made lighthearted jokes about the rainy weather while visiting California. US Photo: Ronald Reagan Presidential Library

Queen Elizabeth inspects a filly foal during a visit to Lane's End Farms in Versailles, Kentucky, on May 24, 1986. AP

Bill Clinton, the US president at the time, and Britain's Queen Elizabeth II smile for the cameras before a celebratory banquet for the 50th anniversary of D-Day on June 3, 1994. AFP

The queen and then-president Gerald Ford dance during a state dinner in Washington on July 17, 1976. AFP

Queen Elizabeth visits Yosemite National Park in California in 1980. AP

Princess Elizabeth poses with Harry Truman, the US president at the time, in October 1951 at the White House. AFP

Ronald Reagan, the US president at the time, and first lady Nancy Reagan pose for photographers with Queen Elizabeth and Prince Philip at a state dinner on March 3, 1983, in San Francisco, California. AP

Queen Elizabeth and Prince Philip join Nancy Reagan during a red carpet celebrity-filled event at 20th Century Fox studios on February 27, 1983, in Los Angeles, California. Getty Images

Queen Elizabeth greets schoolchildren at the state capitol building in Richmond, Virginia, May 3, 2007. AFP

The queen meets singer Frank Sinatra as well as Perry Como, Dionne Warwick and George Burns in Long Beach, California, on February 27, 1983. Getty Images

Queen Elizabeth smiles as she is shown a pair of boots in Austin, Texas, on May 20, 1991. AFP

The queen and Prince Philip visit Jamestown, Virginia, in 2007. PA

Queen Elizabeth and Prince Philip view the Apollo 14 module and space shuttle model in Downey, California, on February 28, 1983. Getty Images

The queen and Prince Philip meet British Nasa astronaut Mike Foale in Houston, Texas, on May 20, 1991. AFP

George Bush, the US president at the time, and the queen wave to the crowd before the start of the Orioles v Oakland Athletics baseball game in Baltimore, Maryland, on May 15, 1991. AFP

Bush and his wife, Barbara Bush, arrive at a dinner at the British embassy accompanied by the queen and Prince Philip on May 16, 1991. AFP

The queen addresses the US House of Representatives on May 16, 1991. AFP

Queen Elizabeth on a visit to then-president Ronald Regan in 1983. US Photo: Ronald Reagan Presidential Library

Queen Elizabeth wrote a heartfelt letter after her California visit. US Photo: Ronald Reagan Presidential Library

Former Virginia first lady Anne Holton with then-governor Tim Kaine hosted the queen and Prince Philip at the Virginia State Capitol in Richmond, Virginia. Visions of America / Universal Images Group / Getty Images

The queen attends the 133rd Kentucky Derby in 2007 at Churchill Downs in Louisville, Kentucky. Getty Images / AFP

Prince Philip and the queen enjoying the 133rd running if the Kentucky Derby. Getty Images / AFP

“We join the world today in mourning the loss of such an incredible human being,” Ms Johnston said.

Queen Elizabeth and Prince Philip stopped at Dry Tortugas National Park and Fort Jefferson, 113 kilometres west of Key West in the Gulf of Mexico, on the royal yacht.

They were welcomed by then-Florida Keys Mayor Wilhelmina Harvey, who presented them with a conch shell, an enduring symbol of the island chain.

The red, yellow, black and white Southernmost Point marker, a 20-tonne concrete monument that resembles a giant marine navigational buoy, was installed in 1983 and has become a popular photo stop for travellers.

Plans call for the memorial to Queen Elizabeth to stay in place through her funeral on Monday.