What is the archaeological evidence for Sodom and Gomorrah?

It's worth noting that it would appear from the text that the Cities of the Plain (which include Sodom and Gomorrah) were destroyed by some type of meteor impact. If so, it's not likely that there was much left behind for modern archaeologists to find, especially considering the primitive state of construction technology back then.

If a meteor were to wipe out a modern metropolis, full of reinforced concrete and steel, I'd expect to be able to come back a few thousand years later and find evidence that there was once a city there. But a bunch of communities with buildings made of wood and clay wouldn't stand a chance of surviving an impact event with a kinetic yield measured in increments usually reserved only for describing nuclear weapons, even as ruins.

A lot has happened in the 11 years since this question was asked.

Beyond Today Magazine's January–February 2022 issue has several articles specifically on this topic, plus some about other Biblical archaeology discoveries.

(Note that the PDF version includes more photographs than the individual article links.)

Here are some highlights:

For the last 16 years archaeologist Dr. Steven Collins, executive dean at Albuquerque’s Trinity Southwest University, and a team of staff and volunteers have been excavating a site they believe to be biblical Sodom. The excavation site is on the east side of the Jordan Valley in the nation of Jordan, across the Jordan River from Jericho.
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Remarkably, the biblical account of destruction from the sky turned out to be supported by numerous lines of geochemical and material evidence buried below the surface of the ground.

Something had demolished the upper 40-some feet of the four- to five story palace structure and blasted away the massive 13-foot-thick mud brick defensive walls of the city. The few skeletal remains showed “fragmentation” and “extreme disarticulation”— meaning the bodies had been violently ripped apart.

A carbon-and-ash-rich destruction layer contained concentrations of shocked quartz, melted pottery and mud bricks, diamond-like carbon, soot, iron- and silicon-rich spherules and spherules from melted plaster. Traces were also found of melted platinum, iridium, nickel, gold, silver, zircon, chromite and quartz.

Heating experiments indicate temperatures must have instantly exceeded 3,600° F (2,000 °C). How hot is that? Enough to turn a truck into a molten pool of iron!

Dr. Allen West of the CRG says of the findings: “Among more technical evidence, we discovered human bones that had been splattered by molten glass from the event. The glass is indistinguishable from that found at ground zero after atomic explosions. These people were killed by the heat and pressure of an atomic-like explosion but without the radiation”

Dr. Silvia has produced 14 lines of evidence that support this site as being the location for the ancient city of Sodom. The paper is available for free download from Nature Scientific Reports (at nature.com/articles/s41598-021-97778-3).

Key finds of the scientific study done at Tall el-Hammam are documented in the research paper—along with graphs, charts, equations and analysis—showing why the site of Tall el-Hammam could very well be the destruction site of ancient Sodom. Some of the key finds include:

• Evidence for high-temperature burning of the city.
• Melted construction materials.
• Minerals and materials subjected to extremely high pressure and temperatures.
• Human bone fragments in the destruction layer.
• High salt content of the soil associated with the destruction and its implications for agriculture in the region.
• Destruction and burning of nearby Jericho at the same time.
• Potential causes of the city destruction

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The Bible gives us other clues about the location of Sodom and its surroundings. Genesis 14:1-17 records a brief war between city-states. From Mesopotamia came kings of Babylon and nearby countries with their forces. Another local alliance of the rulers of Sodom, Gomorrah, Admah, Zeboiim and Bela/Zoar, who had been subject to the Mesopotamians, rebelled when the first group was returning from a military campaign in the south.

They battled in the “Valley of Siddim,” referring to the area surrounding the Dead Sea (verses 3, 10). The ruler of Sodom was defeated along with his allies, and the victors headed north with their plunder—which included Abraham’s nephew Lot among the captives taken. Abraham pursued them with his own small private army, overtook them and rescued his nephew.

From this account we learn more about Sodom. It was part of an alliance with four other cities that were “joined together” in this area, showing they were near each other (verse 3). Also, when the Bible repeatedly links two cities or towns together, as we see with “Sodom and Gomorrah” in this chapter and more than a dozen other places in the Bible, this indicates that the two are geographically very close to one another—typically only a mile or two (or less) apart.

From the site of Tall el-Hammam, which a growing number of scholars are accepting as the location of ancient Sodom, one can see several mounds in which the remains of other ancient cities are buried, including one about a mile north that may be Gomorrah. Others nearby may well be some of the other “cities of the plain.” Archaeological evidence shows that all these cities, along with dozens of smaller towns and settlements in the area, were abandoned at the same time and not resettled for the next 300 to 600 years.

While not conclusive, this evidence is certainly consistent with the likelihood that Tall el-Hammam could indeed be the location of ancient Sodom. …
We discover yet another clue centuries later when the Israelites were preparing to enter the Promised Land from what is today the Hashemite Kingdom of Jordan. Numbers 21 recounts part of their journey, including a stop at Pisgah, which is very near Mt. Nebo—a popular tourist stop today and the spot where Moses looked across the Jordan Valley to the Promised Land before his death. The key phrase to note here is in verse 20, where Mt. Pisgah “looks down on the wasteland”—speaking of the Jordan River Valley spread out below it.

Of itself this doesn’t seem to mean much. But keep in mind that, centuries earlier, Abraham and Lot had looked across that same valley from the opposite (western) side and it was described as “well watered everywhere” (Genesis 13:10) and like the Garden of Eden. But now it is described as “the wasteland.” The lush, well-watered valley that looked so attractive to Lot was now, centuries later, a desolate, abandoned wasteland! What had happened between those two events? The Bible tells us. God rained fiery destruction on Sodom and Gomorrah and the nearby cities and villages, burning them to ash and cinders. It became a wasteland, and it was still a wasteland centuries later.