A gigantic orange Amazon locker has appeared near the Ferry Building in San Francisco, and nobody knows why. Or rather, some people know why, but they sure aren’t telling.

The locker will be the center of an event tomorrow, according to a report by the Wall Street Journal, though it’s unclear just what that event might entail. Based on what I saw today when I stopped by, it seems large enough to house a car, or another, similarly-sized object. And it’s in an area of San Francisco that is usually teeming with people during the day.

The locker, which is appropriately named “giant,” hasn’t shown up on the list of Amazon Lockers available in the city. It’s unclear what the locker’s contents are, though they should be big.

The contraption is about seven feet tall, and a few yards long on each side. There’s a gigantic door on the front, and a smaller, standard-sized door in the back with a deadbolt on it and an extension cord running inside. If there isn’t a car in there, I don’t know what it could be.

The sheer size of the thing gives the box a gravitational pull of sorts. People walking by definitely passed closer to it just to try and see what it is.

Amazon has something of a history with putting cars in boxes. Last year, people who ordered a Nissan Versa through a special promotion from Amazon and Nissan received their car in a massive Amazon box.

We’ll be watching tomorrow to see how the locker saga shakes out. In the meantime, let us know in the comments what you think could be inside Amazon’s big orange box.