Of all the places Scott Fox, 62, could have spent his summer, the one he picked was the excavation of ancient Tiberias on the shore of Lake Kinneret, where a sweltering 40 degrees Centigrade is not unusual.

Fox knows all the Jewish mother jokes. He's the son of one, which might be why he's a doctor, a lawyer, and the owner of a successful bagel company in Cape Cod.

"I always said I wanted to be an archaeologist, but my mother said a Jew should be a doctor," he recalled. "So I became a doctor, and when I retired, I came to the dig. This is what I really love."

The dig at Tiberias begins at 4:45 A.M., but even then, the heat is merciless. By noon, the unbearable heat has driven the dozens of workers and students away from digging for Tiberias' golden age - the Early Muslim period.

Israeli archaeology is sometimes said to ignore the Islamic period in favor of monumental construction from the Roman-Byzantine periods. Sometimes Islamic archaeological strata have paid the price, by being removed without enough attention being paid to them.

The structure now coming to light at the foot of Mount Berenice, south of modern Tiberias, is a good example. For years, it was thought to be a Byzantine market, although some excavators were bothered by the fact that it did not resemble other markets.

Then, in 2009, Dr. Katia Cytryn-Silverman of Hebrew University, which is sponsoring the dig together with a consortium of donors, came to the site. With her expertise in Islamic archaeology, she recognized the building's true nature.

In fact, the large structure is neither a market nor Byzantine. Rather, it is a remnant of a magnificent eighth-century mosque, 90 meters long by 78 meters wide.

Cytryn-Silverman, who now heads the Tiberias excavation, said the building resembles the Great Mosque in Damascus, Syria. There is also a similar mosque in Jerash, Jordan, which is smaller than the one in Tiberias. The mosques tells the story of the hierarchy of the three cities at the time: capital city (Damascus ), district capital (Tiberias ), and outlying town.

A church that predates the mosque has also been uncovered at the site. Unlike at other sites, however, the mosque was built not over the church, but nearby.

The eighth century was Tiberias' golden age, as shown by both excavations and historical writings. A large Jewish community also flourished in the lakeside city, and that community produced the copy of the Bible that became known as the Aleppo Codex.

In short, Tiberias may have been the most tolerant city the Middle East has ever seen.

Cytryn-Silverman said the city's importance can be seen in the historical sources, which say Muslim scholars streamed there to study. The Metropolitan Museum of Art in New York displays magnificent reed mats produced in the city. The previous head of the excavation, the late Prof. Yizhar Hirschfeld, found a cache of gold coins in 2006, and his predecessor, Prof. Gideon Foerster, found a cache of fine jewelry.

"We have a great deal of evidence of the city's material and spiritual flourishing at that time," Cytryn-Silverman said. "It was very beautiful and very multicultural. Jews, Christians and Muslims lived here together. We are trying to understand this coexistence."

The answer might be found in the writings of the 10th-century CE geographer Al-Maqdisi, who described the inhabitants as a bunch of hedonists driven out of their minds by the heat: "For two months they dance; for two months they gobble; for two months they swat; for two months they go about naked; for two months they play the reed flute; and for two months they wallow in the mud." He then goes on to explain: "They dance because of the fleas; they gobble the fruit; they swat the flies; they go naked because of the heat; they play the reed flute - [meaning] they suck on sugar cane; and they wallow in the mud during the rainy season."

The great mosque, which symbolized the power of Muslim Tiberias, stood for 330 years, until an earthquake toppled it in 1068. "The earthquake did not necessarily end life in the city, but the central government was no longer stable," Cytryn-Silverman said. "There were quite a few raids by Bedouin, and the city was unable to recover from the crisis."

In 1099, the Crusaders conquered Tiberias and used the mosque's building stones for another structure. That, too, has been uncovered by the dig, and by the type of clay vessel found there, has been shown to be a sugar cane production plant, part of one of the country's most important export industries at the time.

Since excavations began in 1952 - when the city fathers' plan to build a sports center at the site were stymied by the first discovery of antiquities - successive generations of archaeologists have revealed a theater, a city gate, a bathhouse and other finds, most of which can be seen in the site's archaeological park. But the mosque is outside the park.

Cytryn-Silverman hopes that some day soon, the park will be expanded to include the mosque. Dave Antebi of Haifa, a master's student who is participating in the dig, offered a hopeful scenario: "Perhaps we have come to a stage where we can face other cultures, not only the ones that prove our right to exist here."