The old New synagogue is the oldest functioning synagogue surviving in Europe. Serves are still held there each day, and shabbat. It was built in 1270, before the second world war only the shul in Worms was older, but that was destroyed by the Nazis, so the Old New took it's place.
There are many reasons for the Name 'Old New'. The most logical is that there were three synagogues, Old new was the middle one of them in age so it took the name 'old new' to distinguish it from the other two.
Famous rabbis who are said to have worshipped there are Rabbi Yehuda Lieb Ben Bezalel, aka Maharal during the 1600 century. He was the creator of the Golem who is said to reside to this day in roof of the synagogue.
The Prague community has existed for at least a thousand years, in the area surrounding the synagogue. At the end of the 19 century the Ghetto was pulled down, only the shuls remained. The building surrounding the synagogue have all been rebuilt in a Prague art deco style. It is a paradox, during the time of the ghetto this was the most undesirable area of prague to live. These days it is the most exclusive and expensive. Pariska Street stands to the eastern side of the synagogue and these days contains the kind of shops you find in Mayfair London, and the best places of Paris and New York.