Sumiko IV was the fourth planet in its star system. This planet was home to the Cliffs of Heaven and an Emerald Wading Pool.
The Cliffs of Heaven were recreated in Holodeck Program 47-C aboard the USS Enterprise-D. In 2368, Kristin was injured twice while diving from the cliffs on Sumiko IV. (TNG: "Conundrum")
A simulation of the Emerald Wading Pool on Sumiko IV was also available aboard the USS Enterprise-E in 2373. (Star Trek: First Contact)
This planet was only mentioned in dialogue.
The script originally referenced the Cliffs as being on Cirrus IV, and the Emerald Wading Pool being on Sumiko III. [1] The final cut of the episode instead referenced the Cliffs as being on Sumiko IV and the Wading Pool on Cirrus IV. However, a display of holoprograms seen in Star Trek: First Contact, apparently working from the script, listed a wading pool at Sumiko IV after all.