Cellular reception in many areas is negatively affected by terrain features such as hills and valleys, but distance plays the biggest role in limiting cellular communications, especially in rural areas. The farther you are from a cell tower, the weaker your signal will be.
Hills, trees and buildings all interfere with the quality of the cellular signal between your phone or data card and the cell tower. You may be relatively close to a cell tower but unable to connect because of obstructions. Stucco and concrete walls used in homes, offices and other buildings block cellular signals making it difficult to make a call.
