From WoWWiki

Crystal Lake is a lake directly east of Goldshire in Elwynn Forest. It is crawling with murlocs and may be quite dangerous for an inexperienced adventurer.

Trivia

It may be named after the infamous Crystal Lake from the Friday the 13th movies. In Demon Soul players like to use the Deviate Ninja Transformation to Look more like Jason and rise up out of the lake.

Subzones of Elwynn Forest

Brackwell Pumpkin Patch • Crystal Lake • Eastvale Logging Camp • Echo Ridge Mine • Fargodeep Mine • Forest's Edge • Goldshire • Hall of Arms • Heroes' Vigil • Jasperlode Mine • Jerod's Landing • Library Wing • Lion's Pride Inn • The Maclure Vineyards • Main Hall • Mirror Lake • Mirror Lake Orchard • Northshire Abbey • Northshire River • Northshire Valley • Northshire Vineyards • Ridgepoint Tower • Stone Cairn Lake • The Stonefield Farm • Stormwind City • Thunder Falls • Tower of Azora • Westbrook Garrison