Experts discover hidden secrets in 400-year-old map that could solve 'America's greatest mystery'

Experts believe they may have uncovered the fate of what happened to a group of US settlers who seemingly vanished in a short period of time over 400 years ago.

In the modern world, we have a multitude of ways to keep track of things, making recording history a lot easier than its ever been. I mean, the majority of people can record a HD video to their phone of everything happening and keeping a virtual diary has never been easier.

This certainly wasn’t something that could be done 400 years ago - which leads us to the mystery that researchers have debated for hundreds of years.

What happened to a group of colonists that arrived at an island between North Carolina and the Outer Banks to establish the first permanent English settlement in 1587?

The fort written in 'invisible ink' is just right of the i, in the centre on the left of the map (British Museum)

There were just over 100 English settlers who arrived in Roanoke, but they seemed to disappear leaving little to no trace a few years later.

The theories surrounding their disappearance paint a rather bleak picture for the people, as researchers have suggested that they were killed by native Americans, hostile Spaniards or died off due to famine, disease or natural disaster.

However, now experts believe that a map, titled ‘La Virginea Pars’ may hold the answer and can solve the mystery of the Roanoke colony.

The map was drawn by cartographer and governor John White, who'd established the colony and later discovered their disappearance upon his return in 1590 - finding only the word 'CROATOAN' carved in a tree, according to National Park Service.

The map depicts parts of the North Carolina shoreline running from the north-eastern community of Currituck down to the midpoint of the coast.

However, back in 2012, researchers found a hidden detail on the 400 map and believe it paints a picture on what could have happened to the settlers.

This 16th-century map of what is now coastal North Carolina appears to show a fort concealed under a patch and visible only by backlighting (British Museum)

When placed on a lightbox, hidden in invisible ink were the outlines of what appear to be two forts, one 50 miles west of Roanoke, with invisible ink being thought to have been used in hopes to guard information about the colonies from the Spanish.

"I think we just discovered the intended site for the 'Cittie of Raleigh,' the colony that John White was sent to Virginia to found." curator Kim Sloan told Popular Mechanics (via GB News).

Over the years, European ceramic fragments have been found in and around the area where the fort is thought to have been, known as Site X, helping give validity to the idea.

According to archaeologist Nicholas Luccketti, the pottery discovered was 'limited to the earliest settlement sites in Virginia, possibly dating back to the sixteenth century'.

A further investigation found items that are believed to have been owned by Roanoke settlers, like a shoelace tip and tenter hook, with The New York Post reporting that while it's believed Roanoke settlers could have camped there, it's unlikely that it was the entire colony.

However, there are those that doubt this possibility as the word 'CROATOAN' was the name of another island just south of Roanoke and a Native American tribe that lived there.

This has been interpreted as an indication that they simply moved there after fleeing their original settlement.