Electromagnetic surveys are a fast method of locating and mapping some large earth features such as leveled mounds and refilled ditches. They can be a substitute for resistivity surveys and are particularly suitable where the surface soil is dry, hard, or rocky, or where the vegetation is moderately dense. As in all geophysical techniques, it is necessary that the features to be located are sufficiently different from the surrounding terrain. Results from three sites illustrate the capabilities of electromagnetic surveys. -- AATA