The remains of 17th century mikvas baths at the Great Synagogue of Vilna, Lithuania. Jon Seligman

Ritual baths have been excavated at the Great Synagogue in Vilnius, Lithuania, after the building was destroyed by Nazis during the Holocaust and then the Russians during the country's Soviet years.

The Great Synagogue of Vilna, in Vilnius, was built in 1633 on the remains of an older Jewish prayer house. Much of the building was constructed below ground, as it was forbidden for a synagogue to be taller than the churches of the city. It was three stories high from ground level, with a further two stories below it.

In the Second World War, the Germans occupied Lithuania in 1941.

"During the liquidation of the Small Ghetto, the Great Synagogue was burned and then ransacked," Jon Seligman of the Israel Antiquities Authority, leader of the research team, told Haaretz.

But the shell of the building survived the end of the war. It would not survive the Soviet regime that followed, however.

"In the 1950s, the Lithuanian Soviet government decided to destroy the synagogue and the whole the area around it," Seligman said.

The surroundings included a school, library, kosher meat stalls and the ritual baths, or mikvas. But despite this destructive effort, the building that housed the baths has been partially preserved. The original tiling and drain can still now clearly be seen for the first time in more than 60 years.

Initial investigation of the Great Synagogue of Vilna began in 2011, revealing that some elements of the building had survived. Following this, archaeologists used ground-penetrating radar equipment to guide further excavation of the site.

This was carried out using an architectural plan from the 19th century, which described ritual baths. The baths were reportedly not the most picturesque place to visit when they were functional.

"The walls were covered with black mould and there were grasshoppers running around. Frogs croaking in the corner. It does not sound like it was a very nice place to visit," said Seligman.

Alongside the Israel Antiquities Authority, researchers from the Lithuanian Cultural Heritage Organization and Hartford University participated in the excavation.

Great Synagogue of Vilna
Archaeologists have used ground-penetrating radar to map the ruins of the Great Synagogue of Vilna. Wiki Commons