Complex sentence: The scroll was found in 1952 in Cave Q3 at Qumran the first cave to be explored by archaeologists, the last of 15, and is thus referred to as 3Q15.
Split into simpler sentences: The scroll was found in 1952 in Cave Q3 at Qumran the first cave to be explored by archaeologists. It was the last of 15 scrolls discovered in the cave, and is thus referred to as 3Q15.