With its dark alleys, underground tunnels, and shadowy figures, New York City is no stranger to strangeness. Here are five mysterious events that actually took place in New York City. Some remain unresolved and unexplained to this day; all are eerie enough to make you consider the city in a whole new way.

With its dark alleys, underground tunnels, and shadowy figures, New York City is no stranger to strangeness.

Here are five mysterious events that actually took place in New York City; they remain unresolved and unexplained to this day.

Martha Wright Disappearance From Lincoln Tunnel

In 1975, Jackson Wright and his wife Martha were driving through the Lincoln Tunnel from New Jersey to New York City when Jackson pulled the car over inside the tunnel to wipe condensation from the car’s windshield. To speed things along, he took to the front windshield while Martha worked on the rear window. Moments later, Jackson turned around to find his wife had vanished without a trace. Jackson reported no other cars in the tunnel at the time of her disappearance, and nowhere she could have run to or been snatched away in such a short amount of time. A police investigation ensued, but Martha was never found.

Manhattan’s Mole People

Beneath the hustle and bustle of the city lives an underworld of Gothamites known as the Mole People. The true and harrowing existence of New York’s homeless sub-population of pallor complexioned underlings has been documented by journalist Jennifer Toth in the book, “The Mole People: Life In The Tunnels Beneath New York City.” Based on her research and reporting, it’s believed that the Mole People have lived their lives in secret hovels in the undercarriage of the city’s subway system since the early 90s, free to do as they please away from the New York that rejects them above ground. Toth’s account is grim and shocking – these underground inhabitants forage, eat rats, and even take on creature-like physical appearances due to their sun starved plight, a la sci-fi populations like H.G. Wells’ Morlocks in “Time Machine.”

Toynbee Tiles

These messages of unknown origin are embedded in the streets of Manhattan (there are over 50), a flummoxing conspiracy that’s had curious followers scratching their heads for decades. Buried beneath the asphalt the tiles surface over time with wear and tear, becoming a naturally strange part of the landscape. The linoleum tiles, which have mysteriously cropped up in busy intersections in various cities across the world, all bear strange messages along the lines of:

TOYNBEE IDEA

IN KUBRICK’S 2001

RESURRECT DEAD

ON PLANET JUPITER

What does it mean? It’s a little philosophical, a little sci-fi, tiles touting bizarre political theories and ideologies, possibly referencing British historian Arnold Toynbee, or Ray Bradbury’s “The Toynbee Convector,” as well as Stanley Kubrick’s film, “2001: A Space Odyssey.” There are theories, but no one knows for certain who is behind the tiles and what they mean. There’s even a documentary dedicated to the lore of the tiles, called ‘Resurrect Dead.’

Mystery Booming Noise In The Sky

Starting around 2011, multiple New York City residents across the boroughs have reported hearing unidentifiable “booming” or “rumbling” noises from the sky, and they all insist it is not thunder, construction work, or any other explainable phenomena. One man who uploaded a video to YouTube of the mystery noises in his Brooklyn neighborhood reported that people he knew “across the water in Jersey, and in other parts of Brooklyn,” had heard the very same booming noise where they were. It is uncertain what might be causing these sounds, leaving residents unsettled and determined to find answers. Is it UFOs? Sonic booms? No one is quite sure what the noises are or what they mean, and cases of these strange noises have still been reported as recently as June 2015.

Columbia University Tunnel Network & A Slain Security Guard

A vast underground tunnel system exists beneath Columbia University’s Morningside Heights campus connecting several school buildings. The tunnels beneath Buell Hall measure only a few feet wide, and it is speculated that the building was formerly an insane asylum. Under Pupin Hall, scientists once used the tunnels as a meeting place in the beginning stages of the Manhattan Project. In an effort to keep rogue and nefarious tunnel travelers off the campus, use of the tunnels is now largely forbidden, with ramped up security to dissuade would be tunnel journeymen from stirring up trouble. One such security guard, Garry Germain, was slain execution style in 1988 while on his standard night security shift. Thorough investigations revealed no forensic evidence, no weapon, no discernible motive, and no viable entrance or exit for the killer. One of the only possible explanations is that the perpetrator might have entered the campus undetected via the tunnel system. To this day, Garry’s murder remains unsolved.