Blast-resistant foundations are presented that can be used to support a tower, a building, a building supporting a tower, and a tower supporting a building. These foundations can be transported to an installation site and rapidly deployed. They are comprised of one or more precast foundation blocks that do not penetrate the ground beneath them, do not require adjacent foundation blocks to be bound to one-another at their sides with interconnecting steel, and do not require the buildings and/or towers they support to use guy-wires. They can include protected cavities that contain utility equipment and supplies, and they can include conduits from these cavities that can be extended upward through one or more legs of a tower.