Completed in 1910, the original Pennsylvania Station was once a triumphant welcome to New York City for commuters and tourists alike. Travelers emerged from their trains under canopies of glass into a hall with ornate architecture based off the Roman baths of Caracalla.

Demolition on the Charles McKim-designed station, with its granite walls and 150-foot-high vaulted ceilings, began on October 28, 1963—55 years ago this week. A perfect storm of unfortunate circumstances—declining train ridership, out-of-control maintenance costs, and no laws preventing the destruction of architecturally significant buildings—led to its demise. (In 1965, the Landmarks Preservation Commission was established largely due to the city’s remorse over destroying the station.)

The station that replaced McKim’s masterpiece, meanwhile, is difficult to navigate, plagued by ailing infrastucture, and ill equipped to accommodate its 600,000 daily travelers. Relief will hopefully come in 2020 with the opening of the $1.6 billion Moynihan Train Hall. (One of the centerpieces of the hall’s design? A glass canopy meant to recall McKim’s original design.)

But one thing commuters may not realize: Penn Station never closed while it was being demolished, and much of the structure below the grand old terminal survived the demolition. Pieces of the old station still exist to this day—you just have to know where to look. Here are some of the easiest relics to locate the next time you’re passing through Penn.

Coal power plant

On West 31st street between Seventh and Eighth avenues, a large classical building sits about midblock. That was once a coal-fueled power plant for the original Penn, which helped to power trains as well as provide electricity and heat to the station itself.

The plant stopped functioning in the years after Penn was demolished, but the building, which sits unused, gives a sense of the architecture and scale of the original station. It’s constructed from the same Stony Creek pink granite, while Doric pilasters and generous windows covered with iron cages recall the classical inspiration of McKim’s design. It currently does not have landmark status.

Granite eagles

On Seventh Avenue between 31st and 33rd streets, flanking the entrance to Madison Square Garden and Penn Station, are two granite eagle statues. These eagles once sat proudly atop Penn Station along with 20 similar sculptures, which clocked in at 5,700 pounds each. They functioned both as a symbol of the might of the Pennsylvania Railroad, as well as another reference to classical iconography: The Caesars used eagles to symbolize their capturing of a new territory.

Iron screen

If you use the Long Island Rail Road frequently, chances are you’ve seen an iron screen with beveled-glass windows and an intricate leaf pattern. (If you’ve never seen it, head to the base of the escalators that connect the Amtrak and LIRR areas. It’s right by the men’s bathroom.) As the old station was being demolished, this screen was walled off and encased in construction for the new station. Decades later, while Penn Station was being remodeled, the screen was discovered standing in place. The happy accident was cleaned up and restored to what you see today.

Vintage staircases

There are a few staircases that lead to train platforms that look different from the utilitarian ones commonly found in Penn Station. These vintage modes of egress, which were part of the old station, usually have big brass handrails and more intricate ironwork.

There are a couple of especially noteworthy ones to look for: The first, across from an Auntie Anne’s stand, leads to Track 17. This staircase has a partial screen and spear molding still intact; that molding was used in fencing that would run along the edge of the upper concourse.

The second one leads to tracks 13 and 14. There’s some iron scrollwork at the base of the staircase, from which a lantern would have hung. This is the only extant staircase with the scrollwork still intact that we know of.

Glass-block flooring

Unlike the windowless modern station, Charles McKim’s Penn Station was filled with light. Travelers would board their trains under a canopy of iron and glass, which let sunlight pour into the station. The floors were made up of glass blocks, which allowed light to filter through to the track level.

The glass-block flooring wasn’t removed during demolition; instead, it was painted and tiled over. However, much of it is still visible from the train platform level. The next time you’re on a track, look up—chances are you’ll see the pieces of glass that once flooded the platform with sunlight.

Service area on Track 21

There’s an unassuming beige service area, no longer in use, located at the end of track 21. The facade is subdivided into recessed panels, and the doors have simple but elegant molding.

These are the most easily accessible remnants, but there may be others—we’ve heard that there’s an original track marker still in place by Track 1 and baggage claim, along with areas where you can still see vaulted tile ceilings. Do you have a favorite relic that we didn’t mention here? Let us know in the comments.