The area has been sealed off for decades after it was discovered in the early 1900s (Pictures: YouTube)

Egypt’s ‘Area 51’ is just three miles away from the Giza Pyramids and could have been a mysterious ‘gateway to the stars’.

Some speculate the structure could just be an unfinished pyramid,but others think it served a ceremonial purpose.

Now,unearthed photos from researcher Derek Olsen have gone viral online,showing the T-shaped pit,named Zawyet El Aryan,in solid limestone.

The pit stretches nearly 100 feet deep and has granite blocks lining its sides. Archaeologist Alessandro Barsanti first discovered it in the early 1900s.

Graffiti inside the chamber reads ‘Seba’,which is thought to be the ancient Egyptian term for ‘gateway to the stars’.

Even more odd,a large oval vat with a granite lid sits in the centre of part of the complex – and once contained an ‘unknown substance’.

Ancient Egypt’s mysteries have long been tied to aliens (Picture: Alamy)

Olsen believes the T-shaped pit could have been used as a means to travel through space or serve a spiritual purpose for ancient peoples.

In the 1960s,the Egyptian military took over control of Zawyet El Aryan and banned the public from touring,along with no researchers allowed to enter the site.

Barsanti said of his discovery: ‘I hope that the best informed amongst the tourists will come to admire the monument: the pleasure they will experience during this trip is worth the two or three hours it will take.

‘The size and richness of the materials,the perfection of the cuts and joints,the peerless finish of the granite tank,the boldness of structure and the sheer height of the walls,everything comes together to compose this so far unique ensemble.’

There are fears that Zawyet El Aryan could currently be in poor condition – the military built bungalows over the site and allegedly uses the large shaft to dump waste.

As for its ancient purpose for alleged space or spiritual travel,that still remains unknown.

The real Area 51,however,is a United States Air Force base in the Nevada desert,which the Air Force has had since 1955. It’s classified as a Military Operating Area.

While Area 51,officially called Groom Lake or Homey Airport,has never been declared a secret base,its existence was only publicly confirmed by the CIA in 2013,and all the research conducted there is classified as Top Secret/Sensitive Compartmented Information.

The secrecy which surrounds the base has given rise to a number of conspiracy theories,many of which revolve around the existence of aliens.