The Old Jewish Cemetery lies in the Josefoy, the Jewish Quarter of Prague. It was in use from the early 15th century (the oldest preserved tombstone, the one of Avigdor Kara, dates back to 1439) until 1787. Its ancestor was a cemetery called "The Jewish Garden", which was found in archaeological excavations under the Vladislavova street. The numbers of grave stones and numbers of people buried there are uncertain, because there are layers of tombs. However, it has been estimated that there are approximately 12,000 tombstones presently visible, and there may be as many as 100,000 burials in all. It is not clear when exactly the cemetery was founded. This has been the subject of discussion of many scholars. Some claim that the cemetery is over 1000 years older than the accepted date, which is the first half of the 15th century. The oldest grave belongs to the Prague rabbi and poet Avidgor Kara from 1439. It was founded by the king Ottokor II of Bohemia. According to halakhah, Jews must not destroy Jewish graves and in particular it is not allowed to remove the tombstone. This meant that when the cemetery ran out of space and purchasing extra land was impossible, more layers of soil were placed on the existing graves, the old tombstones taken out and placed upon the new layer of soil. This explains why the tombstones in the cemetery are placed so closely to each other. This resulted in the cemetery having 12 layers of graves.