The artefacts are thought to mostly date back to the New Kingdom (1570 to 1070 B.C.) and Hellenistic era (323 B.C.E. to 31 B.C.E.) but some of the earliest pieces are more than 5,000 years old.
Egypt's Minister of Antiquities Khaled El-Enany described the find as a "museum by itself."
The findings were made at Saqqara—a site that once served as the necropolis for the Ancient Egyptian capital of Memphis.
The Egyptians mummified all manner of animals, including cats, dogs, falcons, monkeys, snakes, crocodiles, cows, and many others.
Scientists in France scanned the 2,500-year-old artifact to see what was inside for the first time since the animals were entombed.
Hieroglyphs on the coffin say it contained a high priestess called Mer-Neith-it-es from 600 BC.
The elegant pictorial writing system of the ancient Egyptians has fascinated generations of archaeologists.