The majority of people think that drones are the future for small package transporting, but I think that they are not cost effective, and the problem would be solved more efficiently with a network of high tension cables. Drones present several problems. - battery life management - air traffic management - inicial cost and mantainance of each drone and each charging station The pain of the first two can be reduced with drone AI in the future, but reducing the cost of maintaining the fleet won't be so easy. It's important to remember that most of the small packages will be commodities. low price = lot of volume = lots of drones = high costs low price = low margin = low revenue to pay those costs I think that it would be way more cheap to connect the rooftops of some strategic buildings with high tension cables and transport small packages hanged through the cables like on a zip line Advantages Routing packages through a network is easy and simple, no AI, just physical routers like the internet. The cost of a package that can obtain energy from a cable and move a wheel is way lower than a drone. Maintainability is better as it's simple There is no battery as cables carry the energy, you can transport a small fridge easily for example There is more security as if a package fails, it's hanged up and carried by the others As an initial starting point, we could just connect the warehouses in the exterior of the city to warehouses in the interior of cities located within flats as we could deliver the packages directly from the network to a warehouse flat. A constant autonomous supply from the exterior would reduce the need and cost of space within the city, and the cost of transport as carriers would have to work in shorter distances and quickly from the city warehouses to the client. Cities wouldn't pose much resistance as it would help them reduce traffic and pollution relatively easy. I missing see some important problem that I can't see?