An archaeologist from the University of Santo Domingo named Kathleen Martinez has been looking for Cleopatra's missing tomb for almost 20 years. She thinks she has now achieved a significant breakthrough.

The Egyptian Ministry for Tourism and Antiquities recently announced that Martinez and her team had discovered a 1,305-meter (4,281-foot) tunnel that was 13 meters (43 feet) underground, which an architect has dubbed an "engineering miracle".

"The excavation revealed a huge religious center with three sanctuaries, a sacred lake, more than 1,500 objects, busts, statues, golden pieces, a huge collection of coins portraying Alexander the Great, Queen Cleopatra, and the Ptolemies," Martinez told CNN.

"The most interesting discovery is the complex of tunnels leading to the Mediterranean Sea and sunken structures," she added.

Read next: Mummy of historical Egyptian Queen Nefertiti soon to be identified

The next phase of her quest, which started in 2005 to find the missing tomb of the Egyptian Queen, will involve investigating these submerged constructions. "My perseverance cannot be confused with obsession. I admire Cleopatra as a historical character. She was a victim of propaganda by the Romans, aiming to distort her image," Martinez said.

"She was an educated woman, probably the first one who studied formally at the Museum in Alexandria, the center of culture in her time," according to Martinez, who said she admires Cleopatra as a student, a linguist, a mother, and a philosopher.

According to popular belief, after her husband, the Roman General Mark Antony passed away in her arms in 30 BCE, Cleopatra promptly killed herself by allowing an asp to bite her. Though the incident has been captured in literature and art for more than two millennia, little is known about the location of their remains.

Read next: Dream discovery: Egyptian professor discovers new ancient sarcophagus

Martinez theorizes that Cleopatra might have done so to reflect the legend by interring her husband in the temple. No other location, building, or temple, according to Martinez, "combines so many conditions as the temple of Taposiris Magna" out of the 20 temples in the Alexandria area that she has investigated.

She claimed that she is currently starting "a new journey" involving underwater excavations.

According to a statement made by the Ministry of Tourism and Antiquities, earthquakes have repeatedly pounded Egypt's coastline over the years, causing portions of the Taposiris Magna to crumble and submerge beneath the waves.

This is where Martinez and her team are looking next. Although it is "too early to know where these tunnels lead," she is hopeful. That said, if the tunnels lead to Cleopatra, "it will be the most important discovery of the century," she said.

Read next: Egypt unearths 250 mummies in ancient necropolis