Game of Thrones is one of the most popular TV shows of all time. Since the fantasy series was released on HBO in 2011, the show continued to grow in popularity as it encapsulated its viewers with intense action, delicate political scheming, and shocking events such as the Red Wedding. However, one area that Game of Thrones doesn't often get credit for is horror. The world of Game of Thrones is vast and full of terrors, some of which did not make it into the TV show (or even the books as of yet).

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This article will list 10 of the most terrifying places left out of Game of Thrones. 

Asshai

Asshai by the Shadow is one of the most mysterious and eerie places in the world of Game of Thrones. The city is at the easternmost and southernmost point on the map of the known world and is bigger than King's Landing, Old Town, Volantis, and Qarth put together. The city, despite being huge, is sparsely populated. There are no children in Asshai and people walk around wearing veils, shielding their faces from the city. The city is also made entirely from a greasy black stone with unknown origin, giving the city a dark atmosphere.

It is said that magic is very powerful in Asshai with shadowbinders and mages making it their home, which is why Melisandre, Marwyn the Mage, and Mirri Maz Duur have all been to Asshai.

Isle of Faces

Isle Of Faces in Game Of Thrones

We don't really know what the deal is with the Weirwoods. We know that they act like an information bank, allowing the children of the forest and the Three-Eyed Ravens to access its knowledge but, aside from this, we know nothing of where they came from or what their goal is.

What is clear, however, is that the Weirwoods have a history of blood magic. People used to sacrifice humans to the Weirwoods and Brynden 'Bloodraven' Rivers seemed to be being consumed by the tree in his cave. The area with the most Weirdwoods is known as the Isle of Faces and is a holy place in Westeros, although it is undoubtedly an unsettling location due to the number of mysterious Weirwoods on its soil.

Heart of Winter

This one may be controversial as an area that could have been the Heart of Winter was shown on the show in season 4, where the Night King turned one of Craster's sons into a White Walker. Although, this has only been claimed to be in the Lands of Always Winter.

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The Heart of Winter is said to be the home of the Others and has only been seen in Bran Stark's fever dream in A Game of Thrones. While the area wasn't seen in the show, George RR Martin has hinted that the books may visit this location.

Mantarys

Mantarys is a city in Essos that used to be part of the Valryian Freehold and is the central surviving city in the Lands of the Long Summer. While the city was fortunate to survive the Doom of Valyria, after the cataclysm, the city gained a reputation for its monstrous and deformed inhabitants. Some believe that the Doom of Valyria caused the Mantarys' inhabitants to become deformed in a similar manner to how radiation effects people.

In a Dance with Dragons, after Dany sends envoys to Mantarys in the hope of finding a new ally, the former Valyrian city returns the envoys' pickled heads.

Skagos

If you hear that there are unicorns on Skagos, you may be forgiven for believing the island is some kind of paradise; however, you could not be more wrong. While there may be unicorns on the northern island, there is little else to make the island a holiday destination.

While, theoretically, Skagos is part of the North, the area and people are despised by those on the mainland. It is rumored that the Skagosi practice cannibalism in the winter, lure ships to their shores so that they may murder the sailors, and sacrifice humans to the Weirwoods.

Yeen

Yeen is a ruined and mysterious city with unknown origins on the continent of Sothoryos. The continent itself is unnerving and monstrous as it is home to Wyverns, bloodflies, and the brindled men. However, Yeen is terrifying for an entirely different reason.

The city, despite being in the middle of the jungle, isn't entirely overgrown with jungle vines. Areas of the city are constructed out of a mysterious, greasy black stone that even the jungle refuses to touch. Perhaps the scariest tale from this eerie city comes from Princess Nymeria. The Rhoynar Princess attempted to settle a group of Rhoynar in the city, but every man, woman, and child vanished overnight.

Cannibal Bay

The Shivering Sea is one of the most unnerving locations in the world of Game of Thrones. There are reports of ice dragons flying over the sea, as well as leviathans and krakens. However, one location in the far north of the sea that may be scarier than those beasts is Cannibal Bay.

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The Bay is an area in the far north that, due to sub-zero weather conditions, traps ships. There are legends that a thousand ships remain in Cannibal Bay, crewed by the offspring of those who sailed in originally. The Bay is so named because the residents of the bay are said to eat one another to survive.

Nefer

Nefer is a port city in the far east of Essos, located just south of the Thousand Islands. Nefer is known as the 'Secret City' due to the fact that nine-tenths of Nefer is said to be underground, which is why the city only appears to be a small town to those traveling past it by sea.

In addition to its secrecy, the city is said to be home to a myriad of necromancers and torturers. Further, the Thousand Islands that lie above the city are also said to be home to a race of green-skinned people that worship fishy gods and sacrifice travelers to their gods.

Five Forts

The Five Forts of Yi-Ti is one of the most mysterious places in all of Essos. It is said that the Five Forts guard the continent against the demons of the freezing desert beyond the forts. Perhaps the Five Forts, like the wall, are intended to keep the White Walkers out of Essos, much like the Wall keeps them out of Westeros; after all, George RR Martin has said his world is round.

Either way, it doesn't matter if the demons of the freezing desert are white walkers or not, they must be terrifying creatures to require such a structure to keep them out.

Stygai, The Heart of Darkness

Stygai, otherwise known as the City of the Night, is a city in the Shadowlands of Essos. While Shadowbinders may venture into Asshai, they do not go near Stygai. The city is said to be haunted, with demons and dragons calling the city their home. Due to the fact that no one wishes to visit this cursed place, not much is know about Stygai.

Some refer to Stygai as the Heart of Darkness and this raises interesting parallels with the Heart of Winter mentioned earlier in this article. Perhaps the two are linked in some way, as the Wall and the Five Forts appear to be.

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