Ruling 2427
If a man or a woman does not perform ṭawāf al‑nisāʾ,[1] which is one of the rituals of hajj and al-ʿumrah al‑mufradah,[2] then sexual activity is not lawful for them until they perform ṭawāf al‑nisāʾ. However, if they marry, then in the event that they had performed ḥalq[3] or taqṣīr[8] and come out of the state of iḥrām, their marriage is valid even if they have not performed ṭawāf al‑nisāʾ.
—Ayatullah Sistani, Practical Laws of Islam, Marriage
This is an obligatory circumambulation (ṭawāf) of the Kaʿbah that is performed as part of the hajj rituals.
Al-ʿumrah al‑mufradah refers to the recommended pilgrimage to Mecca that is performed independently of hajj at any time of the year.
Ḥalq is the shaving of the head performed by men as part of the hajj rituals.