 They recorded that the lake was a "huge sea" ("hanhai") and designated it the North Sea ("Běihǎi") of the semimythical Four Seas.The Kurykans, a Siberian tribe who inhabited the area in the sixth century, gave it a name that translates to "much water".Later on, it was called "natural lake" ("Baygal nuur") by the Buryats and "rich lake" ("Bay göl") by the Yakuts.