Amazon has some towering ideas for drone delivery.

The e-commerce giant filed a patent application for a "multi-level fulfillment center" that would allow drones to deliver packages in urban areas. Basically, it sounds like a giant robot-powered tower that would make it easy for drones to zip in and out as they deliver packages around a city.

There's a "growing need and desire to locate fulfillment centers within cities, such as in downtown districts and densely populated parts of the cities," Amazon says in the patent application, published Thursday by the US Patent and Trademark Office along with several other drone-related applications by the company.

The other patent applications, which were earlier spotted by The Mercury News, cover things like drone performance and noise control. Amazon didn't immediately respond to a request for comment.

Of course, patents are no guarantee this drone tower will become a reality, but Amazon's been pursuing drone deliveries in recent years. In March, the company's drone delivery arm, Amazon Prime Air, shipped its first package out in public in the US. Amazon, UPS, Google and others are also developing drone delivery tech in hopes of bringing shipments to customers more quickly and cheaply.