Let's Go Temple Mount Underground

This illustration from this book (Plate XXVII), "Jerusalem Explored, Volume II with Plates, Being a description of the ancient and modern city, with numerous illustrations consisting of views, ground plans and sections"

appears today in Arnon Segal's weekly Temple Mount column in Makor Rishon.

The author, Ermete Pierotti, is seen there on the left.  In 1858, the Italian Ermete Pierotti, former Captain in the Corps of the Royal Piedmontese Army Engineers, was appointed architect and engineer of Jerusalem by the Ottoman governor. This gave him the opportunity to explore various places in the city, including the Haram al-Sharif (Temple Mount), something which hardly any non-Muslims had done at the time. 

The two arrows at left and right point to a subterranean tunnel under the Dome of the Rock structure.

The solid-colored arrow in the center points to two underground caves, one under the other. The uppermost one is called by the Arabs as the Well of the Souls and it is under the Foundation Stone rock 

which was where the Altar was placed when the Temples stood

.

Pierotti claims that he descended into the second cave below and, as he records in Volume I, p. 97-98:

...I found the floor covered with wet mud to a depth of about 1-1/2 feet. At the first glance I saw an opening on the south side, 3 feet wide and 4-1/2 high, half built up with Arab masonry, and after clearing away some of the stones, earth, and mud that blocked it up, I passed through it into another cistern in the same direction, 32 feet deep. These are both very ancient, and are wholly excavated in the rock; and I have no doubt that they belonged to the threshing-floor of Araunah the Jebusite. On the south and on the east of the deeper cistern are the openings to two passages; the first leads to a conduit (3 feet wide and 3-1/2 high), descending from the west; but after going a few feet along the passage we find another conduit of the same size as the above, coming from the south,[Pg 98] and leading upwards into a double cistern, as I had always expected. The form of the lower chamber is an irregular sphere, about 22 or 23 feet in diameter, its floor is covered deep with dry mud with a few stones, (but rather too many for me to remove). On a careful examination I saw, at a height of 12-1/2 feet, the mouth of the hole leading to the upper chamber, about 6-1/2 feet in diameter and 4 feet long, and the marble slab, which we have already mentioned as covering it. This it was that the Santon struck with his foot or stick to prove the existence of the 'Well of the Souls' below! There is a conduit on the south, into which I entered through an aperture (now walled up), and by a very gradual ascent reached the other extremity at the fountain opposite to the mosque el-Aksa. The whole depth of the double cistern is 28-1/2 feet below the top of the rock, and 23-1/2 below the pavement of the mosque. The reader may imagine my joy at this result of my labours, so long desired and so anxiously sought, and the gratitude I felt to God for granting me this boon of ascertaining the position of the altar of burnt-offerings, and the cisterns and conduits for blood belonging to the ancient Temple; an ample recompense for all my toil. It is true indeed that after a most careful search I have not been able to find any opening on the south-west, in accordance with the statement of the Rabbinical writers; but for this time I trust my own eyes, and that suffices me.

If only we could reinvestigate.

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