A fleet for delivering packages comprising a first number of containers, each container comprising at least one compartment for receiving packages at a main distribution center. The container comprises a first attachment member on an outer surface and a second attachment member on an outer surface. The fleet comprises a second number of long-range transports, each long-range transport is configured to carry multiple containers from the main distribution center to an intermediate distribution center, each long-range transport comprising multiple first attachment receivers, whereby the multiple containers are attached to the long-range transports during transport from the main distribution center to the intermediate distribution center. The fleet comprises a third number of short-range tractors, each short-range tractor is configured to carry at least one container from the intermediate distribution center to delivery destinations for the packages in the container, each tractor comprising at least one second attachment receiver, whereby the at least one container is attached to the short-range tractor during transport from the intermediate distribution center to the delivery destinations and back to the intermediate distribution center. The third number is at least twice as large as the second number and wherein the first number is at least twice as large as the third number.