For decades, the principals at a boxy, two-story kindergarten in downtown Vilnius, Lithuania's capital, unwittingly pored over their lesson plans just a few feet above one of the city's most sacred sites.Today there is a gaping 10-foot hole in what used to be the principal's office, exposing masonry that once was the back of the bimah, the central platform from where the Torah was read in the city's 17th century Great Synagogue. A team of archaeologists from Lithuania, Israel and the U.S. made the discovery this summer."I was relieved because now we know that there is something left," said Justinas Racas, one of the archaeologists who dug up the bimah. "The Great Synagogue was one of the biggest buildings in the Old Town — and one of the oldest. It's very important — not only for Jews but all people living in Lithuania."Before World War II, Vilnius was a center of Jewish life in Eastern Europe. During the Holocaust, the Nazis murdered 90 percent of the city's Jews and destroyed their houses of worship. After the Soviet Union took over Lithuania in 1944, the Communists bulldozed the remains of the Great Synagogue and built a kindergarten on its ruins.It's hard to imagine how the Great Synagogue once rose over a dense cluster of smaller buildings, including the famed Strashun Library, a bathhouse, schools and administrative offices. The kindergarten, which was closed last year, is hidden from the main street by drab postwar buildings. During the summer, archaeologists dug trenches crisscrossing the kindergarten playground, exposing tiles from the bathhouse and the brickwork of cellars.The excavation, financed by Lithuania's Good Will Foundation, a Jewish compensation fund, began in 2016. Racas hopes it will continue for two more summers.As a Catholic Lithuanian, he says it's important to him personally to take part in unearthing a lost piece of his country's past. A century ago, 40 percent of Vilnius' population was Jewish, and there weremore than 100 synagogues in the city."I'm happy that we're discovering this rather painful page of our history about the presence, and disappearance, of the Jewish community in Vilnius," said Inga Merkyte, a Lithuanian archaeologist living in Denmark who stopped by the excavation site during a visit back home. "I think it's a great loss."Lithuanians have long seen themselves as the victims of Nazi and Soviet aggression. But in 2016, a quarter-century after the country regained its independence, writer Ruta Vanagaite published a book that focused on the role of ordinary Lithuanians in perpetrating the Holocaust. Vanagaite faced widespread condemnation, and her book divided the nation.Anna Avidan, the head of a Lithuanian Jewish cultural organization, says Vanagaite's intentions may have been good, but her tone was too accusatory and put many Lithuanians on the defensive. A psychologist by profession, Avidan says Lithuanian society requires "subtle therapy" to come to terms with its past.Even Jewish children who attended the kindergarten in central Vilnius didn't always know the Great Synagogue had once stood there, says Avidan. During the Soviet era, she says, she hid her Jewish roots because of discrimination. When the Soviet Union fell apart in 1991, many Jews took the first opportunity to emigrate, mostly to Israel and the United States."It's really a paradox, because the times now are favorable for Jewish life to prosper," Avidan said. "But there are no people here."Today there are no more than 3,000 Jews left in Vilnius, according to Avidan, compared to a pre-war population of some 70,000.The absence of the Jewish community marks Vilnius like an invisible scar. Jewish holy places that the Nazis didn't raze to the ground, like the Great Synagogue, were later destroyed by the Soviets, who propagated Communist ideology over religion.The gargantuan Palace of Concerts and Sports was built on top of the city's old Jewish cemetery. Tombstones were flipped on their faces and used as steps for the Palace of Trade Unions, another landmark of Communist Vilnius. Some of them have since been returned and lie before the now-abandoned concert hall.One of the last living Jewish sites is the Choral Synagogue,the city's only working synagogue. On a weekday, a dozen older men shuffle over its wooden floors for evening prayers led by Cantor Shmuel Yatom.Yatom comes from a long line of cantors who used to live in Hannopil, in present-day Ukraine. On high holidays like Rosh Hashanah and Yom Kippur, his grandfather would travel to Vilnius to perform in the city's synagogues. Then, during the Holocaust, Yatom's father saw his parents murdered before his eyes — and escaped only "by a miracle.""For me, it is very important to be present here, and to continue my family tradition," said Yatom.He says he is still inspired by the Jewish spirit of Vilnius."When you walk down these streets, you hear the voices of those prewar cantors, and actually it gives you strength and a hope that carrying on this tradition is not in vain," Yatom said.The excavation of the Great Synagogue may present an opportunity to make that past more tangible.Although there are no concrete plans yet regarding the future of the site, archaeologist Racas would like to see a sort of memorial park, with markers to convey the grandeur of the Great Synagogue.Avidan, the Jewish cultural leader, says a park isn't enough."We have to teach young people about the dangers: how cherishing your nationality can become a nationalistic approach and then can lead to stereotypes and then to violence," she said. "The sites of Jewish heritage, they can teach us these things."Once the excavations are over, Avidan says, the site should become a place of learning and warning — but also a place that celebrates life and draws in people the same way as the Great Synagogue once did. Copyright 2018 NPR. To see more, visit http://www.npr.org/.