The Skull Cave is an area accessible in Stardew Valley. It is located at the northern end of the Calico Desert. To gain access, the player must find the Skull Key, which can be obtained from the lowest level of the Mine. Mr. Qi will reward the player for reaching level 25.
Enemies in this mine are a lot more powerful, and exploration is made more difficult by the fact that, unlike the mine near town, you don't unlock fast-travel points using an elevator. Every time you start, you start from the first floor. Bring lots of healing items if you intend to explore it!