Surface surveys, or ground reconnaissance, are the most common form of archaeological survey, primarily because no special or expensive equipment is generally necessary. When doing a surface survey, archaeologists walk across the survey area, looking for artifacts and surface features. These are then either collected or recorded and then analyzed for site location and type.

A surface survey can be done in either an unsystematic or systematic manner. In an unsystematic survey, an archaeologist wanders through the survey area at will, not following a predetermined sampling strategy. This method can be very useful in situations, such as in canyonlands where the topography is extreme and sites are likely to only be found in narrow strips of accessible land. However, if not used carefully, an unsystematic survey can lead to misleading results. If areas with abundant artifacts are more interesting to the archaeologist, he or she may concentrate on those areas, resulting in more data gathered from areas of high artifact concentration.

This potential bias is moderated in a systematic survey where the archaeologist follows a sampling strategy designed to result in a representative archaeological data. In the United States, this is generally done by dividing the survey area into long transects (lines that cut across the landscape) five to 20 meters apart which are then walked by archaeologists. Alternately, if a more exact sample is required, different sampling strategies are used. The region is divided into units and data is gathered from representative units (see the Sampling Strategies Lab for more detail).

Subsurface testing methods are generally used alongside surface surveys to locate subsurface features. The simplest of these methods involve physically digging holes, bringing dirt to the surface, and inspecting it for artifacts. This can be done with a variety of tools, including soil corers, hand and power augurs, posthole diggers, shovels, and trenching machines such as backhoes. In the United States, digging test pits with a shovel, also known as shovel testing, is the most popular of these physical methods. Shovel test pits tend to be between 25 to 100 cm in diameter (if round) or per side (if square) and generally about a meter deep (much deeper and the diameter of the pit becomes too small to for effective digging). The pits are dug in levels like a site. Artifacts from each level are recorded and, as with other survey methods, the information is analyzed for site location and type.

There are also a number of different types of remote sensing techniques that allow subsurface testing without physical disturbance. Ideally, these allow the archaeologist to look into the ground and see features lying beneath the surface. For example, magnetic surveying uses a device called a Proton Magnetometer to measure the strength of the earth's magnetic field at the surface. When scanning undisturbed homogenous dirt, the magnetometer registers a smooth plane. Any disturbance to the homogeneity of the dirt alters the magnetic reading detected by the magnetometer. Archaeological features that a proton magnetometer can detect include middens, ditches, building walls and foundations, hearths, burned structures, and bricks. For example, the photo to the right is a proton magnetometer map of part of the Big Hidatsa Village site in North Dakota. Magnetic anomalies created by buried remains of earth lodges are represented by the large, light circular features and the fire hearths inside are represented by the smaller, dark features. The same type of features can be found with Electrical Resistivity techniques in which a current is passed through the ground and then measured. Because variations in soil type, water content , and ion content will affect the subsurface resistance experienced by the current, archaeological features and other anomalies can be detected. Ground Penetrating Radar is a similar technique, but instead of an electrical current fed into the ground, an electromagnetic pulse is used. If the pulse encounters an interface between two different materials with different electrical properties, a portion of the electromagnetic energy is reflected back to a receiver.

Unfortunately, because none of these techniques can detect detailed, small-scale features, archaeologists relying on subsurface remote sensing alone would miss many archaeological features. However, these techniques are extremely valuable because they neither disturb nor destroy the archaeological record. Today the technology is bulky, expensive, and limited to ideal conditions; but perhaps someday archaeologists will be able to analyze sites without ever picking up a shovel, instead relying solely on subsurface remote sensing images.