Obviously, what I thought I was seeing was impossible. I was in Egypt, looking at what is most likely the first pyramid built in the world. It is officially called the Pyramid of Djoser, named for the pharaoh who was buried in it, but it is commonly called the Step Pyramid. It consists of six mastabas (rectangular structures with slanted sides and a roof) stacked on top of each other, each one smaller than the one below it, so it looks like a staircase for giants.

Our guide said it weighed 850,000 tons! No one, the guide admitted, really knew how it had been built — the ancient Egyptians had no pulleys, no wheels, and no iron tools. There are theories about using ramps made of sand and lots and lots of men pulling on stones with ropes, but nothing can be proven. Two other theories have been proposed: 1) aliens and 2) angels. Both sounded plausible to me.

Even though no one knows exactly how this pyramid was built, archeologists do know the exact date it was built. It was completed between 2670 and 2650 BCE — in only 20 years. That meant the pyramid in front of me was almost 5,000 years old! In Biblical terms, it was built 27 centuries before the birth of Jesus. In historical terms, the Roman Forum wouldn’t be built for 20 more centuries. Today that Roman Forum is just a bunch of ruins. This structure is standing! Aliens or angels seem to be the only possible answer.

The most iconic picture of Egypt is probably the Great Pyramid complex. Of the Seven Wonders of the Ancient World, it’s the only one still standing. The pyramids are located in Giza, part of the greater Cairo metropolis. Earlier in the day in central Cairo, we had squinted hard and caught a glimpse of them through the Cairo smog.

Though built about 75 years after the Step Pyramid, great strides had been made in those years. These pyramids soared to the heavens in smooth triangular shapes. Originally, they were encased in white limestone with pure gold covering the top (all long since stolen), but knowledge of former glory didn’t take away from this present-day glory. They are magnificent.

The Great Pyramid, our guide said, contains over two million blocks of stone, weighing an average of 2.5 tons, with some blocks at the base weighing 15 tons. It was the tallest building in the world until a church in England eclipsed it in the 19 th century – AD. Then he mentioned that until the early 20th century, tourists could climb to the top. Two Bedouins would hold the tourist’s hands, and another would push from behind. At the top, they would have the opportunity to carve their name in stone.

Of course, I wanted to climb it. Sadly, there were no Bedouins to give me a helping hand and push, but the government had developed a safe passage (following an old grave robbers’ path) across the front, just for modern-day tourists. I took my place in line and joined people ascending through the massive stones. I did the math; the stone blocks under my feet had been placed there 4,604 years ago. I silently thanked the aliens and/or angels.

On our way out, we said hello to the equally old Sphinx guarding the approach to the pyramids. His nose and stylized false beard had fallen off sometime before the 15th century, but he was still handsome and still inscrutable.

My sense of wonder and awe stayed with me for the entire Viking River Cruise that my husband, Joe, and I took in early November. The itinerary began with two days in Cairo. Then we flew to Luxor to board a small riverboat. We spent the next nine days sailing between Luxor and Aswan, visiting temples, tombs, and monuments on both sides of the Nile River. Our Viking guide, an Egyptian with a degree in Egyptology, told us stories of the numerous gods and their adventure-filled (and unabashedly lascivious) lives. He showed us how to read the hieroglyphics carved into temple walls (sometimes right to left, sometimes left to right, sometimes up, sometimes down; it depends). He instructed us in bargaining for scarves, spices, and dresses as we walked through what he called “the obligatory market street” leading to every site. Most of all, he helped us understand the passage of time as we literally stepped through 5,000 years of history.

For sheer size and grandeur, no temples exceed Karnak and Luxor. This vast site was under construction for nearly 1,300 years as it was expanded and modified by several pharaohs, including Amenhotep III, Ramses II, and Tutankhamun. It just got bigger and bigger. A sphinx-lined, 1.8-mile Avenue of Sphinxes originally connected the two temples. Two years ago, the walkway was reopened with an extravagant celebration, including a parade with people wearing pharaonic dress, a symphony orchestra, dramatic lighting, professional dancers, and boats on the Nile. (The best YouTube video on this celebration is at www.youtube.com/watch?v=jA5oSNsty2Y.) Now people can again walk the path of the gods, under the imperious eyes of 1000 sphinxes.

Our necks got tired from looking up. The two colossal statues of King Ramses II are 20 feet tall — and he’s sitting down. Amenhotep III’s statue is even higher at 34 feet. For this statue, 700 tons of red granite was imported from Aswan, more than 500 miles upstream. No one knows quite how it got down to Luxor; both aliens and angels have received credit.

Then there is the famous 82-foot-high obelisk, carved from one piece of pink granite. Originally, there were two obelisks, but the second was sent to Paris in 1833 to thank the French for their help in deciphering the hieroglyphics. Today, it’s in the Place de la Concorde.

While we constantly looked up at Karnak and Luxor, we looked down when we were in the tombs in the Valley of the Kings. These tombs were built for pharaohs and nobles from the 16 th through 11 th centuries BCE, each one chockablock full of gold and treasure. After a burial, tombs were sealed and the entrances artfully covered with sand and rocks, never to be opened again. That didn’t work. Of the 63 tombs found to date, all but one have been emptied by grave robbers.

That one intact tomb was King Tutankhamun’s, an insignificant Pharaoh who ascended the throne at age 9 and died at age 19 in 1327 BCE. So, he didn’t accomplish much during his lifetime, but he left us with a tomb that is one of the most important archaeological sites in the world.

Entering his tomb, we descended steep ramps and the air was hot and muggy. I wondered if archaeologist Howard Carter felt claustrophobic in 1922 as he chipped his way through the rock, without fresh air or light. I wondered what he felt when he cleared the final layer of plaster, stuck a candle in the hole he had made, and saw a room full of gold-covered chariots, alabaster vessels, inlaid furniture, jewelry, a gold coffin, the famous 27-pound solid gold funeral mask, and finally, the mummy itself. Asked what he saw, he reportedly replied, “Wonderful things.” It seemed an understatement.

My favorite temple was Dendera. This temple is remote, and thus not usually included with Egyptian cruises or tours. A Coptic priest’s family shared the temple with us; otherwise, we were free to wander and wonder by ourselves. Every square inch of the pillars, walls and chamber ceilings is decorated with abundant lapsus lazuli blue and gold. Instead of being about death and the afterlife, like the pyramids and the tombs, Dendera is about love. It is dedicated to the goddess Hathor, goddess of pleasure.

Every year, the golden statue of Hathor was carried to a temple where, for 15 glorious days, she was reunited with her husband, the god Horus.

While the gods enjoyed their time together, the “commoners” celebrated the Festival of Drunkenness.

There was more. Dendera is the only temple with images of Cleopatra and her son by Julius Caeser, Caesarion. Also, the temple had the only relief of the zodiac system. However, in 1822, French colonizers removed it from Dendera’s ceiling and hung it in the Louvre. Obligingly, they sent a copy back to Dendera, so I easily found my symbol, Taurus the Bull, looking very handsome.

Throughout the days of exploring monuments, our guide was gently taking us through time. Pharaohs lived and died and their exploits were written in hieroglyphics for us to read today. Temples were built over thousands of years. They were buried in silt and sand, and new ones were erected. Although we had learned to tell a First Dynasty temple from a Graeco- Roman one, the changes felt subtle and timeless.

By the time Dendera was built in 54 BCE, 27 centuries had passed since the building of the Step Pyramid. By 47 BCE, Caesar and Cleopatra had secured the throne of Egypt. The time of the Pharaohs was coming to an end. The old gods were no longer worshiped.

Christianity came to Egypt in the first century AD. Then, in the seventh century AD, Islam swept across the country. Today, the country is 90 percent Muslim and 10 percent Coptic Christian. So, times change.

But being in Egypt made me feel that changelessness is also possible. Intricate tombs are still burrowed into the mountains, and we can climb into them today. Temples dedicated to gods who people worshiped 5000 years ago still stand, ready for us to walk through and gasp in amazement. The pyramids exist.

It all comes down to one question: aliens or angels? Either way, it is magically amazing.