Is it permissible for a woman to perform Hajj without a mahram, with a group of women?

A woman is not permitted to travel except with a mahram. This travel is not defined by a specific distance; rather, anything that is called travel, whether long or short, is prohibited for a woman without a mahram, due to the Prophet, peace and blessings be upon him, saying: "A woman should not travel except with a mahram." Therefore, Hajj is not obligatory for a woman unless she has a mahram with her.