Note 1 at Joh 10:40:The Jordan River was in Jesus' day, as it still is today, the most important river in Palestine. It has three sources. The first and easternmost source is a stream called Banias that flows from a cave in a high cliff near the modern-day town of Banias (ancient Caesarea Philippi, see note 1 at Mt 16:13) at the foot of Mount Hermon. The central and most abundant source is from two large springs that emerge at Tel el-Qadi to form a stream called the Laish, or the Dan. The third source is a river called Hasbani. It is the most northerly and highest source and is longer than the other two sources by about thirty miles.

Six miles south of Banias, these three streams merge to form the Jordan River. From there, it flows 6 more miles into the Hula Valley. The Jordan emerges from the south side of Lake Hula and flows about 15 miles south into the northern side of the Sea of Galilee, which itself is 13 miles long and 686 feet below sea level. After exiting the south side of the Sea of Galilee, the Jordan winds through lush vegetation some 65 miles south, emptying into the north side of the Dead Sea, which is 1,385 feet below sea level. The Jordan is the only river in the world that flows below sea level for most of its course, which is a total distance of 223 miles. The name Jordan itself is taken from a Hebrew word meaning "a descender" (Strong's Concordance). It drops almost 3,000 feet from beginning to end.

The Jordan River valley, especially the lower valley as it nears Jericho and the Dead Sea, is tropical in climate and very fertile.