On Saturday the Golden Gate National Recreation Area tweeted and Instagrammed this disheartening photo of the mess people left behind on the Fort Mason Great Meadow.

We know: the weather is so nice that you just had to go out and enjoy the sun. But seriously, if you're gonna go out then don't leave everything behind!

It's bad enough that Dolores Park has a litany of problems, including a-holes who want to harm children, vandals and feral guinea pigs. Now you want to saddle the Parks Department National Park Service with this mess?

Not only that, the Great Meadow is a popular spot for tourists (who certainly also share the blame for the trash, yes) because of its scenic location. Is that the impression you want to leave on visitors to Our Fine City?

We can do better, San Francisco.

Editor's note: The park area in the post was initially mis-identified as Marina Green, and has been corrected.