Where the Gihon Spring empties at the bottom of the City of David there was a pool where John writes in chapter 9:1-12, that Jesus sent a blind man to receive a miracle.

“He spat on the ground, and made clay of the spittle, and applied the clay to his eyes, and said to him, "Go, wash in the pool of Siloam" So he went away and washed, and came back seeing.” John 9:6-7

The healing power of the Pool of Siloam is mentioned in the writings of the earliest pilgrims. In the 6th century CE Piacenza pilgrim wrote:

“You descend by many steps to Siloam, and above Siloam is a hanging basilica beneath which the water of Siloam rises. Siloam has two basins constructed of marble, which are separated from each other by a screen. Men were in one and women in the other to gain a blessing. In these waters miracles take place, and lepers are cleansed. In front of the court is a large man-made pool and people are continually washing there; for at regular intervals the spring sends a great deal of water into the basins, which goes on down the valley of Gethsemane (which they also call Jehosaphat) as far as the River Jordan.” (Trans. J. Wilkinson)

There are two pools recognized as the Pool of Siloam. Approximately 70 yards apart, the first one is the traditional Pool of Siloam and is sometimes called the Byzantine pool. Next to the pool are the ruins of a church built by Aelia Eudocia Augusta the wife of East Roman Emperor Theodosius II. Pilgrims had long come here to celebrate Jesus' miracle and to receive healing there.

The second one is a newer discovery and is a narrow rectangular channel fed by water from Hezekiah's tunnel. This pool is much larger and monumental, and has three flights of five steps leading down into it. Constructed in the early 1st century CE, it had disappeared under soil and debris by the end of the century. Half of it remains buried under the Greek Orthodox Church's garden, which is a beautiful and fertile orchard due to the runoff that collects in the pool beneath. The new discovered pool is most probably the one where the blind man received his sight.