It is a Pennsylvania coal-mining town that ended up having a GIANT underground fire relatively (30 yrs?)
The fire burns to this day, and the town has been since evacuated.
The fire burns to this day, and the town has been since evacuated.

Alessa Gillespie on Silent Hill in Centralia, PA. (Wikimedia Commons)
ARGUMENTUM_EX_CULO
Isla de las Munecas, the Island of the Dolls in Mexico.
Since that day, he began collecting the dolls and displaying them.
HazMat_Bender
The ocean always freaks me out.

Alessa Gillespie on Silent Hill in Centralia, PA. (Wikimedia Commons)
Theres a storm raging, and the waters are violent.
It is the middle of the night, and everything is pitch dark.
The water is frigid cold and wave upon wave relentlessly hit you under the surface.

Isla de las Munecas. (Wikimedia Commons)
You glimpse the faint light from the moon slightly illuminate the turbulent waters as you struggle to stay afloat.
Gasping for air, you glance around desperately looking for anything that could help you.
As you sink into the dark abyss, the thought of7 milesof water beneath you horrifies you.

(Imgur)
You have no idea of what terrors lurk under you in the darkness.
You struggle to push yourself back to the surface, but your arms and legs have given up….
Anyone would be scared shitless of this.

The “dangerous view” of Chernobyl reactor from Pripyat, Ukraine. (Wikimedia Commons)
LetMeBeGreat
Pripyat, Ukraine.
It was the city next to Chernobyl.
Feldman742
I would say, a few feet away from the infamouselephants footinside the chernobyl reactor.

“Elephant’s Foot” at Chernobyl. (Imgur)
If you look at it, you die.
Even being around a corner doesnt necessarily mean youre safe.
slayemin
Poveglia Island, just off the coast of Italy.

Poveglia Island. (Pixabay)
used by the ancient Romans as a place to quarantine people afflicted by various plagues.
When they died, they were buried in mass graves on the island.
used as a huge quarantine center during the Black Plague.

Tsingy de Bemaraha Nature Reserve, Madagascar. (Wikimedia Commons)
An asylum was built in the center of the island in the early 1900s.
Patients reported seeing paranormal activity but nobody took them seriously.
The clinic was closed shortly thereafter.

Mt. Yasur erupting. (Wikimedia Commons)
Currently, Poveglia is closed by order of the Italian government.
People may not visit the island under pain of imprisonment and heavy fines.
RykonZero
For a different value of scary than most of the posts here, I nominate Mt.

(Flickr)
Yasur on the island of Tanna in Vanuatu.
Yasur is an active, erupting volcano.
Tanna is a remote, off-the-grid island inhabited by, among others, America-worshipping John Frum cargo cultists.

Catacombs of Paris. (Wikimedia Commons)
The air rains thick, gritty ash particles that you shake out of your hair for days.
), but my brain stem did not want to hang around to find out.
Yasur simply doesnt give a shit about you.

Doorway to Hell. (Wikimedia Commons)
It was a great example of what Burke calls the Sublime.
But their peculiarities do add to the sense of profound alien-ness of the place.
ImJKP
Tower of Silenceis the most frightening place I can think of.
jebik
The Paris Catacombs.
They then add to the 6 million lost souls down inside.Six million.
BlooFlea
Deans Blue Holea giant underwater hole into the abyss.
NotMyCircus
Basically thesiteof a Soviet-era gas mining operation, the site was deemed worthless.
The scientists lit the deposit on fire, but it has been burning since the 1970s.
History lesson aside, to this day, the place looks like an opening to Hell.