Never Lake in the opening animation of Sonic CD.
Sonic the Hedgehog CD
in other media
Unspecified region on Earth
In Sonic the Hedgehog CD, a giant metal chain was set up by Dr. Robotnik from a rock formation by Never Lake up to the Little Planet to keep the small satellite from leaving Earth, while the doctor raided it to search for the Time Stones. After said giant chain gets cut by Sonic in the good ending of game, Little Planet is free from Robotnik's control and disappears above the Never Lake.
Never Lake is a very large and beautiful natural lake filled with clear water, and is located in a large region of open landscapes with green fields and some occasional rock formations.
The borders of the Never Lake are all surrounded by steep drop-offs, such as cliffs, meaning it does not have any sort of beach. Surrounding the Never Lake around its borders are also several mountains and large rock formations. The Never Lake itself also has a single river connected to it, though it is unspecified whether it serves to drain or feed the lake.
Apperances in other media
Sonic the Comic
Never Lake appeared in the UK's Sonic the Comic, much as it does in the games universe. When Amy Rose was kidnapped by Metallix, she was taken to Never Lake. This was the site of Sonic's first battle with the Metallix robot.
Later, Chaotix arrived at Never Lake (travelling from the Special Zone by means of the Omni-Viewer) to investigate the activity of the Brotherhood of Metallix on the Miracle Planet. They destroyed a Trooper patrol and also met up with Sonic and Porker Lewis (although Porker was in fact a Metallix robot in disguise).
Spagonia is mentioned in the Sonic the Hedgehog comic book series and its spin-offs published by Archie Comics. In this media, it is a sacred lake in the Kingdom of Mercia, where, much like in Sonic CD, the Little Planet appears above once a year for a month.