There are few monuments in the world that are as iconic as the Pyramids of Giza, a necropolis that dates back nearly 5,000 years.

The Great Pyramid of Giza is the only one of the ancient seven wonders of the world still standing and, in 2007, 100 million people voted to select it as one of the New Seven Wonders of the World.

Many people dream of visiting the pyramids, as well as Egypt's numerous other thousands-year-old historical monuments, ancient temples, and artifacts. I certainly did.

But upon visiting Egypt's many pyramids recently, I discovered something that, in retrospect, should have been obvious: They are not that fun to go into.

Egypt has 138 discovered pyramids, including the Pyramids of Giza. One day last December, I took a full day to visit as many of them as possible.

That included the Pyramids of Giza, as well as the step pyramid of Djoser, the Pyramid of Unas, the Bent Pyramid, and the Red Pyramid.

The first pyramid of the bunch I visited was the Red Pyramid at the Dahshur necropolis, so named for its red limestone stones. It's the third largest pyramid in Egypt and it is free to go inside the tomb when you buy a ticket to the complex.

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In contrast, to go inside any of the Pyramids of Giza, you have to pay US$10-15 a person in addition to your regular ticket to the complex.

It's important to remember that live humans weren't intended to be inside the pyramids. They are tombs, first and foremost, designed to both exalt the deceased and protect their possessions from grave robbers.

To enter the pyramid, I descended a steep staircase in a narrow passageway that travels down a couple hundred feet to a short horizontal passageway.

By the time I reached the bottom of the staircase, I couldn't see the light at the end of the tunnel. When I visited, it was a quiet day and I only had to shimmy out of the way of a few tourists climbing up as I was going down.

As I passed them, I realized that I wasn't going to be able to get out of the pyramid any time soon.

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With more people, I imagine the sense of claustrophobia is even more pronounced.