From publisher blurb:
This is a short encounter set that is systemless and intended for 3rd(ish) level PCs in any OSR-style game. The design is deliberately vague in several areas to make it easy to "tweak & toss" into your current campaign. Perfect for when the party goes "left" when you expected them to go "right", any GM/DM/Judge can easily drop this into the current campaign.
It is intended to print this file two-sided and fold in half, zine-style. This PDF download consists of three pages of content (map, encounter, and basic set-up). There are a couple of hotlinks within the file taking you to the Frugal GM blog where you can download a hi-res version of the map in you so desire.