Fifty years ago this week, a landmark law was passed that went a long way towards preserving the city's history, and a new exhibit opening Tuesday takes a look at the story of historic preservation in the five boroughs. NY1's Roger Clark filed the following report.

The latest edition of Madison Square Garden has been part of the cityscape since 1968. But before that, the old Penn Station stood there. It was demolished five years earlier, highlighting the need for preservation in the five boroughs.  

"There was actual loss, and there was also sort of threatened loss, and finally, the mayor, Mayor Wagner, signed the law into effect on April 19, 1965," said Donald Albrecht, curator of the Museum of the City of New York.

That law first gave landmark status to buildings and neighborhoods to protect them from the wrecking ball. Eight years later, it was expanded to protect public interiors and scenic landscapes.

The law is the focus of a new exhibit at the Museum of the City of New York called "Saving Place." You travel back in time to the beginnings of the preservation movement in the late 19th century, to the impact the law had after its passage and the establishment of the Landmarks Preservation Commission.

"It's divided into various facets that show the battles, some won, some lost, and all of the people involved," Albrecht said.

After the law was passed, there was still work to be done when it came to historic preservation. One case this exhibit chronicles is the effort to save Grand Central Terminal. That went all the way to the United States Supreme Court.

With the help of high-profile New Yorkers like Jacqueline Kennedy Onassis, the court affirmed the public interest in landmarks designations, saving Grand Central and giving a boost to preservation efforts nationwide. The law allows refurbishing of landmarks. which is what happened at Carnegie Hall, and it allows for preservation and growth. Witness the Diane Von Furstenburg studio headquarters built behind landmark facades in the Meatpacking District.    

"Sometimes it's controversial, sometimes it's contentious, but often times, it sparks really interesting, creative architecture that blends the old and the new, and we wanted to show that," Albrecht said.

You can see that and much more about how the city preserves its past heading into the future through September 13.