The very word "Jerusalem", or "yerushalem, yerushalayim" in Hebrew has a lot of mystical interpretations in the Jewish tradition. Thus, it can be a symbol of the earth itself. Also, in Kabbalah symbolism, it is considered to be God's city. It is thought to be the earthly variant of the heavenly Jerusalem, and the main purpose which can be attained through human spiritual development. According to mystical people, Jerusalem is nothing but an earthly paradise place which takes its cue after the one found in God's heaven. In a broader sense, however, the name of the city denotes "the place where later God will show, or make known on earth, the fullness and perfection (shalem) of what is above".
Still in the Jewish mystical realm, the name of the Holy City can be interpreted as having the meaning of "foundation of peace," because its consonants (SHLM) have the meaning of perfect/whole, (shalem) or peace (shalom). This earthly site's peace is represented by Yeru or Yir'eh, which was nothing but one of Jerusalem's seventy names. The Holy Temple in the city of Jerusalem was put down twice. There is only one wall left to symbolize Jewish people's ownership over this beautiful land and over the Old City in Jerusalem, and that one is called The Western Wall or the Kotel HaMaaravi.
The builder of the First Jerusalem Temple, in the 10th century BC, was Solomon. In the Holy Scriptures, we can find Solomon's words referring to this holy place: "May Your eyes be open day and night toward this House, toward the place of which You have said, 'My name shall abide there;' may You heed the prayers which Your servant will offer toward this place. And when You hear the supplications which Your servant and Your people Israel offer toward this place, give heed in Your heavenly abode..." (1 Kings 8:17).
The religious life of Israel got concentrated in the Jerusalem Temple. This turned Jerusalem into an important place of pilgrimage, and also a significant political, economic and spiritual center. Jerusalem became the capital of the United Kingdom of Israel. It was also the place where most of the prophets wrote the spiritual and moral principles that were meant to become the pillars of the Jewish mysticism and spirituality. Things turned bad in 586 BC when Babylonians invaded Jerusalem. Nebuchadnezzar order the city to be torched and therefore they also destroyed the Jerusalem Temple, whereas people there were taken into exile. At that point in history, the Western Wall became Judaism's holiest place and the most worshiped place for Israel and worldwide Jews.
A lot of people of various religious convictions came to the Western Wall, also known as "The Weeping Wall", to place a small prayer written on a piece of paper inside one of the Wall's cracks. The reasons mentioned on these papers vary from prayers for the sick to receiving God's guidance regarding certain problems or to finding one's soulmate. According to many testimonials, there were indeed many wishes fulfilled after placing one's request there. Such testimonials can be found on plenty of independent blog-spots and forums, but also on websites referring to Jerusalem in general or to the Western Wall in particular.
There are also many resources according to which Jerusalem is, in the Jewish mystical tradition, the very place where the Earth's initial construction began, at the Foundation Stone center to be more precise. Naturally, we can ask what the logical explanation given for this theory actually is. Thus, the Holy Land is to be found at the surface of the Earth's central point; also, Jerusalem is found in the center of Israel, and also the Jerusalem Temple can be found in the Holy City's main point.
There are many other significant details which, according to the Jewish tradition, explain why this place plays such an important role in the spiritual life of Israel. Thus, the Holy of Holies in the Holy Temple of Jerusalem was considered to be the very dwelling place for the Shekinah. In Jewish mysticism, Shekinah represents the Holy Spirit manifesting itself as a feminine presence.
This is just the Jewish mystical perspective on the Holy City; let us not forget that this place plays an essential role for Christians also, since there were many events which took place here, if we are only to mention the Calvary or the Resurrection.