Just across the Piscataqua River and Prescott Park sits the eerie abandoned Portsmouth Naval Prison in Portsmouth, New Hampshire.

The towering structure is castle-like in its architecture and has been vacant for over 45 years, according to boston.com.

It's so desolate that locals might not think to notice its presence at this point, as the almost colorless building has silently stood for decades with no signs of life.

How old is the Portsmouth Naval Prison?

The prison has a rich history. Boston.com explains that the facility sits on an island once home to Fort Sullivan during the American Revolution and Spanish-American War.

According to thevintagenews.com, it was decided that a prison would be built on the property after the subsequent Fort Long was disassembled in 1901. The construction of the Portsmouth Naval Prison would be completed seven years later in 1908.

How many prisoners were housed in the Portsmouth Naval Prison?

According to thevintagenews.com, the Portsmouth Naval Prison was initially designated for members of the Navy, but also housed prisoners from the Coast Guard and Marines. More than 2,000 people dwelled inside the Prison's walls during World War I.

Decades later, two wings were added during World War II to accommodate the growing number of prisoners, which would exceed 3,000. Thevintagenews.com stated that in all, more than 83,000 inmates would pass through the prison's doors.

Portsmouth Naval Prison, 1973 (Naval History and Heritage Command)
Portsmouth Naval Prison, 1973 (Naval History and Heritage Command)
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Why was the Portsmouth Naval Prison called the 'Alcatraz of the East'? What were conditions like?

Boston.com explains that the fast-moving currents of the Piscataqua River were an intimidating obstacle for prisoners looking to escape the Prison's island. So, just like Alcatraz, these inmates were trapped by both land and sea.

Conditions inside the prison also fluctuated.

According to thevintagenews.com, criminal activity and poor interactions between prisoners and guards weren't unusual occurrences at first.

In response to this, a theater, YMCA, basketball court, and other programs were added as part of a rehabilitation effort to improve conditions and help prisoners transition back into society.

Theater, 1957 (Naval History and Heritage Command)
Theater, 1957 (Naval History and Heritage Command)
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Cell Block, 1973 (Naval History and Heritage Command)
Cell Block, 1973 (Naval History and Heritage Command)
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Prison Cell, 1972 (Naval History and Heritage Command)
Prison Cell, 1972 (Naval History and Heritage Command)
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Why is the Portsmouth Naval Prison abandoned?

According to Boston.com, it was decided in the 1970's that the prison was no longer needed, and its remaining prisoners were transferred elsewhere.

But deciding what to do with the property has proven to be a complicated question.

The prison's walls not only contain harmful materials like asbestos and lead paint, but portsmouthnh.com states that the entire structure is "too expensive to rebuild or tear down."

So, for more than 45 years, the deteriorating Portsmouth Naval Prison has sat abandoned.

Portsmouth Naval Prison
The Portsmouth Naval Prison as it appears today (Getty Images/iStockphoto)
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Can you tour Portsmouth Naval Prison?

Portsmouthnh.com states that the Prison is closed to the public. It could be challenging to access the grounds as well, as they are on the restricted property of a federal facility.

Is the Portsmouth Naval Prison haunted?

Those intrigued by the paranormal might be curious to know if such a place, with its history and age, is home to paranormal activity. Surprisingly, an internet search doesn't uncover much about alleged ghosts.

That said, Roxie Zwicker of New England Curiosities offers a Wicked Haunted Waterfront Tour, in which she delves into some spooky stories about the shipyard and prison.

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