Jamarat

The three pillars stoned during Hajj: Jamarat al-Aqabah on the 10th, and all three on the days of Tashreeq.

History and Seerah

The three pillars (al-Sughra, al-Wusta and al-Aqabah). A report from Ibn Abbas (RA) says they mark where Shaytan appeared to Prophet Ibrahim (AS) attempting to sow doubt regarding Allah's command, and Ibrahim cast seven pebbles at him at each spot until he retreated in disgrace.