Ian Strathcarron wonders why Baalbek (Baalbec) was included in the Quaker City Excursion tour as it was not a Christian site but was the Roman Empire's "most sacred site of pagan worship". But then Twain did not know it was Roman and could not imagine how it could have been built by mere humans. "The Temples of Jupiter and Bacchus are still standing, just about, and the one to Venus still has its substructure in place. The Temple to Mercury, built on an adjacent hill, has all but disappeared. Later local gods were incorporated into the worship there."
Strathcarron goes on to remark that 30 years after Twain's visit "Kaiser Wilhelm II visited the site and, like everyone before and since, was overwhelmed by the scale of the endeavor. He bought permission from the Ottoman Sultanate to excavate the site, a task since taken over by teams from France as a part of the spoils of the First World War."
According to Strathcarron, the site has been used for worship since 9000 BC, Alexander the Great passed through in the mid 330s BC and the Greco-Roman construction began. Two hundred years later Pompey ordered the greatest amount of building on the site. "The temples took 120 years to build and were only finished when Nero was emperor, in around 60 AD."
He also notes that what Twain called The Temple of the Sun is now known as the Grand Court and what he called the Temple of Jupiter is now know as the Temple of Bacchus.