WHILE MOST mortals think of vacations as a chance to chill out on a beach in the sun, for John Rubbo it was adventure time.

John was a scuba diver who liked discovering shipwrecks in the dark corners of the seas where he loved to swim.

He panned for gold in Alaska, rappelled down the side of the Municipal Services Building, buzzed around in private planes and visited 20 countries.

He once told his family, "There's a big world out there. Go see it."

He died Wednesday at the age of 90.

John's adventurous spirit might have been traced back to his service as a Royal Air Force fighter pilot during the Battle of Britain before the United States entered World War II. He was shot down over the English Channel and broke both legs.

John Rubbo's real first name was Sebastian, but nobody ever called him that. He was known to Philadelphians and mayors for more than 40 years as the man who took meticulous care of City Hall.

A Philadelphia magazine article about him in March 1987 called him "The Man Who Loves City Hall."

"He knew every crevice of the building," said his daughter, Lu Anne Rubbo-Goldfarb.

John worked for the city's Building Services Division and was chief of the Department of Public Property, taking care of all public buildings, but with a special fondness for the 120-year-old gray stone monster, once the tallest building in the world.

He often took visiting dignitaries through the building, familiar as he was with its 700 rooms and 250 sculptures by Alexander Milne Calder, including the 27-foot-tall statue of William Penn on top of the tower.

One of his proudest accomplishments was the construction of the altar and platform on Benjamin Franklin Parkway where Pope John Paul II celebrated Mass when he visited the city in October 1979.

Over the years, John also assisted in the production of feature films shot in Philadelphia. When a movie company wanted to shoot in Philadelphia, he helped them.

Thanks to her father, Lu Anne got to interview John Travolta for her student newspaper at St. Maria Goretti High School when he was in town to film the 1981 movie "Blowout."

Even after he retired, John helped finance, produce and scout locations for several independent films.

John Rubbo wound up in the RAF after English recruiters, desperate for pilots to fend off the German Luftwaffe that was hammering the country, recruited American high school students. John was attending South Philadelphia High at the time.

After recovering from his injuries in the Channel and after the U.S. entered the war, John joined the Army Air Corps and continued to battle the Germans.

After the war, he joined the Naval Reserves. He also flew with the Civil Air Patrol into his 80s.

As a scuba diver, John loved searching the ocean depths for shipwrecks. One he discovered off the coast of Trinidad-Tobago in the Caribbean was named for him - "El Wrecko Rubbo" - on nautical charts.

Oddly enough, John suffered from seasickness on boats, including the Queen Mary that brought him and other troops home after the war, but he quickly recovered once he hit the water, his family said.

He was active with the Philadelphia Seahorses Dive Club, and knew such famous divers as Jacques Cousteau.

John often had private planes, which he kept at the Northeast Philadelphia Airport. One was a Cessna, and Lu Anne recalls when she was about 8, he said to her, "Let's fly to Washington for lunch." And they did.

It was in the '70s when John took off for Alaska to pan for gold. "It was something he always wanted to do," his family said.

The family still has a vial of the gold dust he panned.

John was a true renaissance man. His interests also included painting, woodworking, stained glass, construction, antiques and history. He took up gemology in his retirement.

John was born one of twins in Philadelphia to Antonio and Angelina Rubbo, Italian immigrants. His twin, Michael, died about 25 years ago.

John graduated from South Philadelphia High School and later took courses at Drexel University.

He had known his wife, the former Marian L. Scarlata, since they were children. They married in 1950.

In addition to his wife and daughter, he is survived by another daughter, Eleanor Donaldson; a son, Anthony John Rubbo, and five grandchildren.

Services: Funeral Mass 11 a.m. Monday at St. Richard's Church, 18th and Pollock streets. Friends may call at 10 a.m. Burial will be at Holy Cross Cemetery.