The Sagan in times of flood receives the overflow of the next lake in the series, Chambo or Ganjule, which lies, at a height of 3460 ft., 70 m.
In its lower course it meanders through pleasant pastures, bogland and pine forests in succession, receives the waters of various mountain streams, passes close by Bunzlau and through Sagan, and finally, after a course of 160 m., joins the Oder at Crossen.
In the 15th century it successfully withstood sieges by the Hussites (1429 and 1432), by the Poles (1450) and by the duke of Sagan (1477).
All the lands torn from John Frederick were not, however, assigned to Maurice; he was forced to acknowledge the superiority of Bohemia over the Vogtland and the Silesian duchy of Sagan.
In July 1628 Kepler accordingly arrived with his family at Sagan in Silesia, where he applied himself to the printing of his ephemerides up to the year 1636, and whence he issued, in 1629, a Notice to the Curious in Things Celestial, warning astronomers of approaching transits.