Which of these is Europe's oldest active synagogue?

The Old New Synagogue (Czech: Staronová synagoga; German: Altneu-Synagoge), also called or Altneuschul, situated in Josefov, Prague, is Europe's oldest active synagogue. It is also the oldest surviving medieval synagogue of twin-nave design.

Completed in 1270 in gothic style, it was one of Prague's first gothic buildings. A still older Prague synagogue, known as the Old Synagogue, was demolished in 1867 and replaced by the Spanish Synagogue.

It is said that the body of Golem (created by Rabbi Judah Loew ben Bezalel) lies in the attic where the genizah of Prague's community is kept. A legend is told of a Nazi agent during World War II broaching the genizah, but who perished instead. In the event, the Gestapo apparently did not enter the attic during the war, and the building was spared during the Nazis' destruction of synagogues. The lowest three meters of the stairs leading to the attic from the outside have been removed and the attic is not open to the general public. Renovation in 1883 and exploration of the attic in August 2014 found no trace of a golem.