Isenfel

From Tardis Wiki, the free Doctor Who reference

Isenfel was a planet in E-Space. It was covered in ice. The Fifth Doctor, Nyssa, Tegan Jovanka and Vislor Turlough landed there in search for the dimensional interface that Pik Solus stole. The interface was a lab experiment to simulate the collapse of E-Space, and ways to keep it constant. (AUDIO: Equilibrium)