In ancient Egyptian mythology, the Duat is the underworld or the realm of the dead. It is the home of the god Osiris, Anubis, Thoth, Horus, Hathor, and Ma’at, and many grotesque spirits controlled by them. Ra, the sun god, also travels through the Duat every night and battles the serpent monster Apep.
The most important function of the Duat however is that it is where people’s souls go for judgment after death. Their tombs were viewed to be entrances into the Duat, and they could travel back and forth from the underworld through these burial chambers.
Within the Duat are many impressive geographical features. There are normal features like islands, fields, caverns, rivers, and mounds – but also unrealistic structures like lakes of fire, trees of turquoise, and walls of iron. Once someone had passed away, it was up to them to navigate this tricky landscape to become an akh, or blessed spirit. They had to pass through a series of gates protected by grotesque spirits with human bodies and heads of animals, knives, torches, or insects. Along the way were also mounds and caverns filled with animals or gods who would threaten the dead as they passed.
Once the dead passed all of these unpleasant spirits, if they did, they would reach the Weighing of the Heart. This ritual involved weighing the heart of the deceased against a feather, representing Ma’at – the goddess of truth and justice. This ritual was performed by Anubis. If the heart was out of balance, due to failure to follow Ma’at, then the heart would be devoured by Ammit, the Devourer of Souls. Those who did pass would travel to the paradise of Aaru.
All we know about the Duat and the afterlife comes from funerary texts like the Book of the Dead, Pyramid Texts, Coffin Texts, etc. Each document found giving information about the underworld gives a different persepective on it, and each one tends to be inconsistent with each other. Researchers believe that there is no one uniform interpretation of the Duat.