Amazon has been opening retail locations designed for picking up and returning items.

The retailer has opened at least 30 of these stand-alone locations.

We used one in the Los Angeles area a couple of months ago to see what they're like.

Customers can do only two things at Amazon pickup locations: pick up packages, and return them. That's all they're built for.

But for Amazon, being the online-shopping powerhouse it is, those are two very important purposes.

The locations function a lot like a post office, but just for Amazon packages. Get them sent to the building's address, and they'll be there when you're ready to pick them up. Packages can be kept there for up to two weeks.

Need to return an item? The service is free, since it doesn't actually need to go through the mail.

The pickup locations work a lot like the Amazon Locker system, which offers a place in convenience and grocery stores for customers to pick up packages. But by setting a time limit, the pickup location solves the problem of customers forgetting or neglecting to pick up their packages, something that can render the lockers unusable until some space is freed.

Amazon won't say exactly how many of these locations exist in the United States, but the number is at least 30 and growing.

A few months ago, I visited the pickup location in Westwood, Los Angeles, a stone's throw from UCLA, to see what they're like to use. True to Amazon's ethos, it's simple and basic, but it works extremely efficiently.

It's perfect for a college student without a permanent address, or a tourist like me. One benefit for Prime members is that they can order some items for same-day or next-day pickup.

Here's what it's like to use an Amazon pickup location: