The Kaaba (Arabic: al-ka bah [al Ka'ba], "...

The Kaaba (Arabic: al-ka bah [al Ka'ba], "The Cube"), also referred to as al-Ka bah al-Musharrafah (Arabic: , the Holy Ka'bah), is a building at the center of Islam's most important mosque, Great Mosque of Mecca (Arabic: , The Sacred Mosque), in the Hejazi city of Mecca, Saudi Arabia. It is the most sacred site in Islam. It is considered by Muslims to be the Bayt All h (Arabic: , "House of God"), and has a similar role to the Tabernacle and Holy of Holies in Judaism. Its location determines the qiblah (Arabic: , direction of prayer). Wherever they are in the world, Muslims are expected to face the Kaaba when performing Salah, the Islamic prayer.
One of the Five Pillars of Islam requires every Muslim who is able to do so to perform the Hajj (Arabic: , Greater Pilgrimage) at least once in their lifetime. Multiple parts of the hajj require pilgrims to make Tawaf (Arabic: , Circumambulation) seven times counter-clockwise around the Kaaba, the first three times fast, at the edge of the courtyard, and the last four times slowly, nearer the Kaaba. Tawaf is also performed by pilgrims during the Umrah (Arabic: , Lesser Pilgrimage).However, the most significant time is during the hajj, when millions of pilgrims gather to circle the building during a 5-day period. In 2017, the number of pilgrims coming from outside the Kingdom of Saudi Arabia to perform hajj was officially reported as 1,752,014 and 600,108 Saudi Arabian residents bringing the total number of pilgrims to 2,352,122.

Qibla
The Qibla is the direction faced during prayer.[Quran 2:143 144] It is the focal point for prayer. The direction faced during prayer is the direction of where the Kaaba is.

Pilgrimage
The Sacred Mosque is the focal point of the Hajj and Umrah pilgrimages. that occur in the month of Dhu al-Hijjah in the Islamic calendar and at any time of the year, respectively. The Hajj pilgrimage is one of the Pillars of Islam, required of all able-bodied Muslims who can afford the trip. In recent times, about 1.8 million Muslims perform the Hajj every year.
Some of the rituals performed by pilgrims are symbolic of historical incidents. For example, the incident of Hagar's search for water is emulated by Muslims as they run between the two hills of Safa and Marwah.
The Hajj is associated with the life of the Islamic prophet Muhammad from the 7th century, but the ritual of pilgrimage to Mecca is considered by Muslims to stretch back thousands of years to the time of Prophet Ibrahim.

History
The Quran contains several verses regarding the origin of the Kaaba. It states that the Kaaba was the first House of Worship, and that it was built by Ibrahim and Ishmael on Allah's instructions.

Verily, the first House (of worship) appointed for mankind was that at Bakkah (Makkah), full of blessing, and a guidance for mankind.
Quran, Chapter 3 (Aale-Imran) verse 96

Ibn Kathir, the famous commentator on the Quran, mentions two interpretations among the Muslims on the origin of the Kaaba. One is that the shrine was a place of worship for Angels before the creation of man. Later, a house of worship was built on the location by Adam and Eve which was lost during the flood in Noah's time and was finally rebuilt by Abraham and Ishmael as mentioned later in the Quran. Ibn Kathir regarded this tradition as weak and preferred instead the narration by Ali ibn Abi Talib that although several other temples might have preceded the Kaaba, it was the first "House of God", dedicated solely to Him, built by His instruction and sanctified and blessed by Him as stated in Quran 22:26 29. A Hadith in Sahih al-Bukhari states that the Kaaba was the First Mosque on Earth, and the Second Mosque was the Temple in Jerusalem.