How does the great pyramid differ from when it was first build?

When the Great Pyramid of Giza was first built around 2580–2560 BCE, it was originally covered in highly polished Tura limestone casing stones that reflected sunlight, making it shine brilliantly. Over the millennia, many of these casing stones have been removed or eroded, exposing the underlying core structure made of rougher limestone blocks. Additionally, the pyramid originally stood at about 146.6 meters (481 feet), but has since settled due to erosion and the loss of the outer casing, now measuring approximately 138.8 meters (455 feet). The surrounding landscape and the context of its construction have also changed significantly due to urban development and archaeological exploration.