Romuva or Romowe (known as Rickoyoto in the writings of Simon Grunau) was an alleged pagan worship place (a temple or a sacred area) in the western part of Sambia, one of the regions of pagan Prussia. In contemporary sources the temple is mentioned only once, by Peter von Dusburg in 1326. According to his account, Kriwe, the chief priest or "pagan pope", lived at Romuva and ruled over the religion of all the Balts. According to Simon Grunau, the temple was central to Prussian mythology. Even though there are considerable doubts whether such a place actually existed, the Lithuanian neo-pagan movement Romuva borrowed its name from the temple.
According to Peter von Dusburg, writing in 1326, the name Romuva is derived from the word Rome. He describes the Kriwe as a powerful priest who was held in high regard by the Prussians, Lithuanians, and Balts of Livonia. His messengers were recognized by a certain rod or other insignia. He guarded the sacred flame and could look into the destiny of deceased followers. He received one third of any booty taken by pagan warriors.
This early account was further enhanced by Simon Grunau in the 16th century. He described an eternal sacred fire, an eternally green oak with idols representing a pagan "trinity": Patrimpas (god of spring), Perkūnas (god of thunder) and Patulas (god of the underworld). The place was guarded by priests and vestales. Images appeared based on this description and became very popular with romantic historians. Grunau changed the name for the place to Rickoyoto (from Prussian rikijs - ruler and -ote - a place name ending) and invented the term "Kriwe of Kriwes" (Lithuanian: krivių krivaitis, Latvian: ).