CHICAGO (CBS) — After weeks of speculation, the oldest freighter on the Great Lakes — and one with a special place in Chicago history — is unloading its last load of cement, before steaming to Sturgeon Bay, Wis., to be transformed into a barge.

The freighter known best to Chicagoans as the Medusa Challenger, now the St. Marys Challenger, arrived at the South Chicago Terminal in Lake Calumet around midnight Friday.

A number of the ship’s fans — and she has many — lined bridges along the Calumet River to get late-night photos of the 551-foot-long freighter close-up. The enthusiasts came from as far away as Massachusetts and New York.

“We’re talking about a ship that was built before the Titanic,” said Richard Jenkins, of Lawrence, Mass., who chased the Challenger from Chicago to Michigan and back.

He said the Challenger is the last active U.S. flag freighter built before World War II, and at 107 years, one of the oldest operating ships in the world, which he credited to the fact that for most of her career, she worked on the Great Lakes and not in salt water.

The powdered cement delivery, which was expected to continue until late Saturday afternoon, marked the conclusion of a second career for the freighter, one which began when she was rebuilt for the cement-hauling trade in 1967-68.

She earned a spot in Chicago infamy between 1968 and 1979, when she unloaded regularly at the old Penn Dixie pier on Goose Island. Routinely, bridges that opened as wide as possible to allow her through would become stuck in the up position in her wake.

The Challenger remains the longest ship ever to traverse the Chicago River.

One sailor who worked aboard the Challenger for five years in the 1970s said he was hard-pressed to remember any trip in which at least one bridge leaf did not become stuck.

Beginning in 1979 and continuing until Saturday, the ship’s southern port of call was Lake Calumet, although she also made regular stops in Milwaukee and several other Wisconsin ports, depending on the transportation needs of her owner.

Those who spoke with the crew said the mood on board has become increasingly somber in the past few weeks, as speculation grew about the future of the ship, which is due for a mandatory five-year federal inspection.

Although owner Port City Steamship Services said it was trying to decide between re-engining the ship, the last oil-burning steamship on the Great Lakes, with a new diesel engine and transforming it into a barge, others said Port City made the decision some time ago and already has purchased a tug waiting in Muskegon, Mich., to begin its pushing chores.

The Chicago History Museum is among those hoping to obtain a piece of the ship as it is transformed. Some ship enthusiasts said they understand the dollars-and-cents decision that had to be made, but Jenkins said they should leave the ship as she is.

“She’s kind of special,” he said. “Next year, she won’t be special any more.”

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