Test pits or trenches are open type or accessible exploratory methods where soils can be inspected in their natural condition. The necessary soils samples may be obtained by sampling techniques. The obtained soil samples can be used for finding strength and other engineering properties through laboratory tests. Test pits are considered suitable only for small depths - up to 3m. The cost of the soil exploration increases rapidly with depth. For greater depths, lateral supports or bracing of the excavations will be necessary. Test pits are usually made only for supplementing other methods or for minor structures.