The Baalbek Stones are six extremely large Roman stone blocks located in Baalbek, Lebanon (ancient Heliopolis). These stones are known for their unusually massive size, which is unmatched in ancient history. The stone was cut from nearby hills, and some of the large blocks were only partially shaped from the rock.

Three of the smaller stones are part of a base wall in the Roman Temple of Jupiter Baal (also called Heliopolitan Zeus), known as the "Trilithon." Each of these stones weighs about 750 to 800 tonnes. The quarry where the stones were taken was slightly higher than the temple, so no lifting was needed to move them. The stones may have been rolled along temporary dirt paths from the quarry to their final positions.

The other three stones are large monoliths not part of a larger structure. They are known as the "Stone of the Pregnant Woman" (about 1,000 tonnes), the "Stone of the South" (about 1,242 tonnes), and the "Forgotten Stone" (about 1,650 tonnes). These are the first, third, and fifth largest stones ever quarried in human history. They were likely meant for the Jupiter Baal complex, possibly as an addition to the Trilithon, but they were never moved from the quarry. Some were only partially removed from the rock during ancient times and have not been used since.

Since the 19th century, many archaeological teams, mostly from Germany and France, have studied the site. Research at Baalbek has continued into the 21st century.

Trilithon

The Trilithon (Greek: Τρίλιθον), also called the Three Stones, is a group of three large stones lying flat that are part of the base of the Temple of Jupiter Baal at Baalbek. These structures are located on a hill in the area known as Tel Baalbek. Each stone is 19 metres (62 ft) long, 4.2 metres (14 ft) high, and 3.6 metres (12 ft) thick. Each stone weighs about 750–800 tonnes (1,650,000–1,760,000 lb). The layer of stones beneath the Trilithon includes stones that are estimated to weigh 350 tonnes (770,000 lb) and measure 11 metres (36 ft) wide.

Although these stones do not form a trilithon in the way modern archaeologists define the term, they have been called the Trilithon since at least the early Byzantine period.

Stone of the Pregnant Woman

The Stone of the Pregnant Woman (Arabic: حجر الحبلي, romanized: Ḥajar el-Ḥible), also known as the First Monolith, remains in the ancient quarry, located 900 meters (3,000 feet) from the Heliopolis temple complex. Although the smallest of three monoliths, it is the most famous because it is well-preserved, lies at an angled position, and has never been completely covered by earth.

The block was not fully excavated, as its bottom remains attached to the bedrock beneath it. A study in 2015 found cracks and a flaw on the northwestern face of the monolith, which is on the downhill side and may have been the last part to be excavated.

In 1996, a measuring team from the Austrian city of Linz took measurements at the site to determine the size of the two monoliths and their possible role in building the large Jupiter temple. Their calculations showed the block weighs about 1,000 tonnes (2,200,000 pounds), supporting earlier estimates by Jean-Pierre Adam.

The rectangular stone block is:

There are several stories about the name. One says the monolith is named after a pregnant woman who tricked the people of Baalbek into believing she could move the giant stone if they fed her until she gave birth. Others suggest the name comes from legends that pregnant jinn were responsible for cutting and moving the stone. Another story claims the name reflects the belief that a woman who touches the stone may experience greater fertility.

Stone of the South

The Stone of the South (Arabic: حجر القبلي, romanized: Ḥajar el-Guble), also known as the Second Monolith, was found again in the same quarry in the 1990s. It weighs about 1,242 tonnes (2,738,000 pounds) and is larger than the Stone of the Pregnant Woman. Some confusion exists about its name because its location was forgotten, and some sources say "Stone of the South" is another name for the Stone of the Pregnant Woman.

These are the measurements of the rectangular stone block, assuming the shape is the same in the parts that are still buried.

Forgotten Stone

The Forgotten Stone, also known as the Third Monolith, was found in the same quarry in 2014 by archaeologists from the German Archaeological Institute. Its weight is estimated to be about 1,500 tonnes (3,300,000 pounds).

The stone is 19.6 metres (64 feet) long, 6 metres (20 feet) wide, and at least 5.5 metres (18 feet) high.