ancientegyptdaily:

_{Hieroglyphs in the pyramid of UNAS (c. 2400 bc) at Saqqara. Unas choose to build his pyramid near the southwest corner of Step Pyramid of DJOSER instead of at Abusir with the majority of the Fifth Dynasty Kings. It is the smallest pyramid from the Old Kingdom, but the finest in terms of bas reliefs.}

_{Inside the pyramid archeologists discovered the oldest known religious text in the world, the Pyramid Texts. Although this is the first time the Pyramid Texts were inscribed inside a pyramid, there is evidence that the texts had been in use since around 3200 BCE. Unas’s pyramid also established the typical plan of the internal chambers for pyramids that would be used throughout the end of the Sixth Dynasty.}

_{source}