Triple send-a-prayer offer until 9th of Av

Kotel
The Kotel (The Wailing Wall) is one of the most significant sites for the Jewish people. It is known to be the last remnant of the Holy Temple. The Western Wall is one of the support walls built by order of King Herod (37 BCE) at the time of a general reconstruction of the Temple, undertaken to beautify the Temple and enlarge the Temple Mount.
Jews from around the world come here to pray.  Notes of prayers and requests written to G-d are placed between the ancient stones of the Wall.
Our sages quote a fourth century scholar: “Rav Acha said that the Divine Presence has never moved away from the Western Wall”. Rabbi Jonathan Eybeschutz writes that “after the destruction of the Temple, God removed His Presence from His sanctuary and placed it upon the Western Wall where it remains in its holiness and honor”.

King David
King David (907-837 BCE) was the first king of the Royal tribe of Judah. He was a supremely righteous person and author of most of the book of T'hillim (Psalms). He made all plans necessary for the building of the Temple, but was not given this great merit by G-d because of all the warfare he had conducted during his life.  His son, Kind Shlomo, build the Temple after his father passed away.
King David’s tomb is the traditional place that is considered King David’s tomb.
The final Redeemer will be a descendant of King David.

Or HaChaim
Rabbi Chaim ben Attar (1696-1742) was born in Morocco, moved to Lovorno, Italy, where he briefly served as Rabbi before moving to the Holy Land, first settling in Acre, thence moving to Jerusalem. His resting place is on the Mount of Olives in Jerusalem.
He is known as the "Or HaChaim", the title of is commentary on the Chumash (the Five Books of Moses), a work of great depth and importance, that he authored. The Or HaChaim was a scholar of great stature, in Talmud and Jewish Law (the revealed aspect of Torah) as well as in Kabbala (the esoteric aspect of Torah).