http://www.theblaze.com/stories/2014/09/18/archaeologists-in-poland-make-horrendous-discovery-underneath-the-ground-that-the-nazis-never-wanted-found/

Archaeologists in Poland Make Horrendous Discovery Underneath the Ground That the Nazis Never Wanted Found

Sep. 18, 2014 8:05pm Jason Howerton

Archaeologists in eastern Poland claim they have discovered new evidence related to the Nazi regime’s evil and murderous history.
Hidden underneath the ground at a former Nazi concentration camp on the outskirts of the village of Sobibor, archaeologists reputedly found gas chambers that were intentionally hidden by Nazis after an uprising in 1943. Officials estimate roughly 250,000 Jews were killed in the gas chambers.
Following an uprising at the camp on Oct. 14, 1943, German forces reportedly demolished the gas chambers. The site of the mass killing of Jews was later covered with an asphalt road.

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Credit: Yad Vashem International Institute for Holocaust Research
Yoram Haimi, one of the archaeologists on the project, told Reuters that they “were amazed at the size of the building and the well-preserved condition of the chamber walls.” Officials are now working to establish just how large the gas chambers were, which will give them a better idea of how many people were murdered at the camp.
Haimi also has a personal connection to the grisly discovery. Two of his uncles were reportedly captured by Germans and later killed at the Sobibor death camp.

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This photo taken in Sept. 2014, and released by the Yad Vashem International Institute for Holocaust Research shows a ring discovered near recently discovered gas chambers at the Nazi-era death camp of Sobibor in Sobibor, Poland. Polish and Israeli Holocaust researchers announced Wednesday, Sept. 17, 2014, that they have discovered the exact location of the building that housed gas chambers at the camp. (AP Photo/Yoram Haimi, Yad Vashem International Institute for Holocaust Research)
The Yad Vashem International Institute for Holocaust Research has more information on the extermination camp:
The Sobibór Extermination Camp was located near the village and railway station of Sobibór, in the eastern part of the Lublin district in Poland, not far from the Chełm-Włodawa railway line. The camp was established along with the extermination camps of Treblinka and Bełżec as part of Aktion Reinhard. Built in March 1942, it was basically composed of three parts, each individually fenced in: the administration area, the reception area, and the extermination area. In addition, there was a section of forest in the northern part of the camp where the Nazis had begun to construct a bunker. During the period of the camp’s operation, April 1942 – October 1943, about 250,000 Jews were murdered there. In the wake of the camp uprising that occurred on 14 October 1943, the Germans decided to dismantle the camp. Apart from certain structures that have been dismantled since the war and the few buildings in connection to the camp that are still standing, the site has remained bare lacking any real trace of the former extermination camp.
Another archeologist involved in unearthing the gas chambers, identified as Wojciech Mazurek, offered a bone-chilling description of the concentration camp.
“The extermination of people took place there; murder by smoke from an engine that killed everyone within 15 minutes in these gas chambers, in torment, shouting,” he told Reuters Television. “It is said that … the Nazis even bred geese in order to drown out these shouts so that prisoners could not have heard these shouts, these torments.”
Very few prisoners ever made it out of Sobibor alive. Due to this tragic fact, and because German forces destroyed the camp, there is still much unknown about the infamous site.

Of the roughly 300 prisoners escaped during the 1943 uprising, most were captured and killed. Only 50 Sobibor prisoners came out alive at the end of World War II, according to Reuters.