Cirrus IV
From Memory Alpha, the free Star Trek reference
Cirrus IV is a planet, home to the Emerald Wading Pool.
In 2368, Doctor Crusher recommended a holodeck simulation of the Emerald Wading Pool on Cirrus IV to USS Enterprise-D crewmember Kristin, who had been injured while diving on a more challenging simulation of Sumiko IV. (TNG: "Conundrum")
