The Holy Kaaba
The Kaaba is the center of the Sacred Mosque in Mecca and its most important landmark, as well as the best site to visit in Mecca. The Kaaba is surrounded by a belt of stone known as the Black Stone, a stone that descended from Paradise, as mentioned in the noble Hadith: "The Black Stone descended from Paradise, and it was whiter than milk, but the sins of the children of Adam darkened it." The Tawaf around the Kaaba is a pillar of performing the rituals of Hajj and Umrah.
Zamzam Well
The Zamzam Well is located near the Kaaba, and the water of Zamzam is among the purest waters on Earth. It is a blessed water that sprang from the spot where the foot of the Prophet Ishmael - peace be upon him - stood. It is narrated in the Hadith of Ibn Abbas in Sahih Bukhari that Allah commanded Gabriel - peace be upon him - to cause the earth to gush forth under the feet of the infant, so he struck the ground with his wing, and it gushed forth from under Ishmael - peace be upon him. When the spring appeared, Hagar (fearing that the water would run out) surrounded it with sand and stones. The Prophet ﷺ said: "May Allah have mercy on the mother of Ishmael; if she had left Zamzam or said: if she had not scooped from the water, Zamzam would have been a flowing spring."
The Station of Ibrahim
The Station of Ibrahim is a gem from Paradise; it is an ancient stone that the Prophet Ibrahim - peace be upon him - stood on while building the Holy Kaaba. When the structure rose, he stood on it and handed stones to his son Ishmael - peace be upon him - to place them with his hand to raise the wall. Each time he completed one side, he moved to another, circling the Kaaba and standing on it. Whenever he finished one wall, he moved to the next side until the four walls of the Holy Kaaba were built. The Prophet ﷺ said: "Indeed, the corner and the station are two gems from the gems of Paradise; Allah has concealed their light, and if their light had not been concealed, it would have illuminated what is between the east and the west" (Sunan al-Tirmidhi and Musnad Ahmad).
As-Safa and Al-Marwah
As-Safa and Al-Marwah are the names of two small opposing hills. As for As-Safa, it is the peak of Mount Abu Qubays, and Al-Marwah is the peak of Mount Quaiqan. As-Safa is named because its stones are smooth and hard, while Al-Marwah is named because its stones are soft white stones that spark fire. Al-Qurtubi - may Allah have mercy on him - mentioned another reason for the naming in his interpretation, stating that the origin of As-Safa in the language is the smooth stone, which is a well-known mountain in Mecca, and likewise, Al-Marwah is also a mountain. As-Safa is mentioned because Adam, the chosen one, stood on it, and Hagar stood on Al-Marwah, so it was named after the woman and thus feminized. The Sa'i between As-Safa and Al-Marwah is a pillar of Hajj and Umrah, as they walk between them seven times.