The Old-New Synagogue
 
The Old-New Synagogue was built in an early Gothic style around the middle of the 13th centruy. It was originally called the "New" or "Greate" Shul to distinguish it from an older house of prayer which did not survive. It was not until the 16th century, when other synagogues were established in Prague, that it became known as the "Old-New" Synagogue. It is now the oldest surviving example of the medieval twin-nave type of synagogue. The earliest examples of this type were the Romanesque synagogue in Worms (dating from the 12th century) and the early Gothic synagogue in Regensburg. The hall is vaulted by six 
5-partite vault compartments supported by two octagonal pillars. The Old-New Synagogue, which is not part of the Jewish Museum, is one of three Prague synagogues, together with the High and Jerusalem Synagogues, in which services are held.

The synagogue's real name is in Hebrew: The Al-Tnay Synagogue. Al tnay means in Hebrew "on condition". The tradition says that the synagogue was built with stones from the King Solomon's Temple ruins in Jerusalem and that when the time will come and the Temple will be rebuilt, this synagogue will be dismantled and its stones will rebuild the Temple; this is "the condition". The people who did not understood Hebrew meant that "al tnay" are the Yiddish words "alt neu" = old-new". 

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