Before most excavations take place there are a series of smaller investigations that are undertaken.

Fieldwalking
This is a method of locating finds by walking over the ground. If the area has been recently ploughed or weathered finds may be more obvious.

Geophysical Survey
There are several types of geophysical surveying, but all use the same basic principle. An electric current is passed through the soil and the reflected signals are received and recorded.
Buried features and areas of previous disturbance are then plotted on charts, which are used when deciding what action to take next.