As Long Island has evolved from farmlands and horse carriages to housing developments and congested highways, one piece of infrastructure has stood the test of time - a straight line of train tracks cutting through the middle of the Island.

It is the Long Island Rail Road's main line, stretching from Brooklyn to Greenport. And to commemorate today's 175th anniversary of the railroad, the railroad arranged a historian-guided train ride through the LIRR's long history.

"We're excited about the past and we're excited about the future," said LIRR president Helena Williams, who went along for part of the 95-mile trip, and along the way picked up proclamations from Nassau's and Suffolk's county executives.

The LIRR was chartered in 1834 primarily as a means to ease travel from New York City to Boston. Trains would take passengers from Brooklyn to Greenport, where they would pick up a ferry to Stonington, Conn.

Wednesday's train ride aboard the LIRR's "TC82" inspection car began at the westernmost station on the system's main line, Flatbush.

The original western terminal was at the Brooklyn waterfront, but in 1859, the City of Brooklyn banned steam engine trains, and the LIRR was forced to have horses pull its trains within the city, said David Morrison, an LIRR historian.

The horses were unable to pull the train up Cobble Hill, so the LIRR could no longer travel farther west than Flatbush, Morrison said.

As the train passed through Jamaica, Morrison discussed its transformation from a modest, ground-level station to the "bustling, elevated" junction it is today, Morrison said

"Hicksville had quite the historic significance in the history of the Long Island Rail Road," Morrison said as the train rumbled through the station, built in 1837. "Due to the financial crisis at the time, the railroad didn't reach Greenpoint until 1844. So, for four years, Hicksville was the eastern terminal of the railroad."

In 1955, Hicksville also hosted a ceremony marking the formal end of steam engines on the LIRR, which had changed over to diesel power.

Like so many communities on Long Island, Hicksville developed around the LIRR, as travel to and from New York City was made easier.

"It's hard to imagine what Nassau would look like if there was no railroad," said Nassau Chief Deputy County Executive Marilyn Gottlieb, who met up with the train as it stopped at Mineola. "Probably a lot more cars, and a lot less economic development."

The train continued through Farmingdale station, listed on the National Register of Historic Places. The current station, built in 1895, still houses the electrical substation for the old Halesite-Amityville Trolley, Morrison said.

East of Ronkonkoma station, the main line has remained largely unchanged over the LIRR's life. Diesel powered trains chug along a single, unelectrified track that cuts through woods, horse stables and vineyards.

"This is really the way it looked," said LIRR spokesman and train history buff Michael Charles, who was on board for the ride. "Basically you had farms, pine barrens, and that was about it."

After about four hours, the train reached its final stop.

"This is the end of the line," Morrison said as the train pulled into Greenport station. From its platform you can gaze out at ferries preparing to take passengers across Long Island's waters. "Out here it's not that much different."

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