Stóragjá is a hidden gem in North Iceland, tucked away near Reykjahlíð. This unique rift features a cave filled with naturally-heated geothermal water, but don't be tempted to take a dip—the water's beautiful blue hue comes from dangerous algae and unhealthy bacteria levels. While it may not be as famous as Grótagjá cave from Game of Thrones, Stóragjá is definitely worth a visit for those seeking a quieter and off-the-beaten-path experience in the stunning Icelandic landscape.