Ma'rib is the ancient capital of the Kingdom of Saba and is the most famous archaeological site in Yemen. Whether or not Ma'rib was the home of the Queen of Sheba, as many claim, the region is one of the oldest populated areas in the world. Flint tools suggest that mankind first reached Yemen about 40,000 years ago, and by 1000 BC, several large kingdoms were established in Yemen along the profitable Frankincense trade route. We will visit the ruins of the Sabaean capital and the Temple of the Moon. Nearby, we explore the ruins of a huge earthen dam that was built here in the 8th century BC and fed a sophisticated irrigation system for more than a thousand years. The final collapse of this dam in 570 AD forced the survivors to flee to the far reaches of the Arabian Peninsula. According to legend, it was this catastrophe that is responsible for the spread of the Arab population throughout the Middle East.