Before deciding exactly where and how to dig, an archaeologist formulates specific questions about the past that he or she wants to answer. Only then can the appropriate excavation approach be undertaken.
Archaeologists typically dig in the ground for remains of human occupation. In rare cases (such as Stonehenge in England or the pyramids of Egypt), evidence of past cultures is visible to the naked eye. In some regions (particularly in the Middle East), a tel will also indicate a rich spot for excavation.
Sometimes accidental discoveries by local residents lead archaeologists to important sites. For example, the first Dead Sea Scrolls were accidentally uncovered in 1947 by a shepherd boy chasing after his flock in the Judean Desert. Their discovery led to organized excavations that turned up thousands more scrolls and fragments.
When sites are not clearly visible, historical records frequently help pinpoint the locations of past settlements. Archaeologists also conduct ground surveys, which involve walking across an area to look for surface clues such as potsherds or ashes from ancient hearths. Before a new building or housing development goes up, archaeology teams are often called in to survey the area to determine if there are any sites that might be destroyed by the construction.
In recent decades, archaeologists have developed various forms of "remote sensing" to identify potential sites. These methods include airborne and infrared photography, ground radar, magnetic-field recording, and metal detection.