(a) Abu Salih narrates from Abu Sa'id (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "A woman may not travel a journey of three days or more without her father, her son, her brother, her husband or a mahram."
(b) In the narration of Abu Nu'aym: (She may travel) with her husband, her father, her brother or a mahram.
(c) In the narration of al-A'mash: a journey that is three days or more.
(d) Qaza'ah bin Yahya narrates from Abu Sa'id (may Allah be pleased with him): more than three days, and in one narration: two days. Abu Hurayrah (may Allah be pleased with him) narrates from the Prophet (peace and blessings be upon him): a day and a night; and some narrations mention a day, some a night, and some a barid.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5406