When Link gains access to Lake Floria, he encounters a Parella named Jellyf, who initially fears him and attempts to escape. After realizing that he holds the Water Dragon's Scale, the Parella leads Link through the many enemy-infested areas in the underground Lake. Eventually, Link reaches Faron, who has been attacked by Ghirahim and is now in a weakened state. Though initially disbelieving of Link's claim of being the chosen hero, she sends him on a quest to retrieve Sacred Water in order to restore her. When he does so, Faron takes him to the area beyond the lake, where she opens the entrance to the Ancient Cistern for him.
The Floria Waterfall is located towards the back of Lake Floria. It is here that Faron shows Link the entrance Ancient Cistern.
Lake Floria appears in the game, and is located in the Faron Grasslands region of Hyrule. It is a large body of water fed by Floria River. Much like its Skyward Sword counterpart, it features large waterfalls known as the Floria Falls. Furthermore, the Floria Bridge is a large wooden bridge that spans the entire lake from east to west supported by three large trees.
It is possible that Lake Floria may have become the Zora's Domain or Lake Hylia. This is supported by the fact that Lake Floria is the only large body of water seen during the events of Skyward Sword, and its location relative to the overall map is similar to the location of Lake Hylia in other games in the Zelda series. In addition, the underground cavern of Lake Floria bears some resemblance to the appearance of Zora's Domain.
However, during the events of Breath of the Wild, Lake Floria, Zora's Domain and Lake Hylia appear as three geographically distinct locations, making this theory less probable.
Floria comes from the Latin word meaning "flower", possibly referring to the lush nature of the lake's surroundings, or the flower-like rock formations within the cavern.