The Karnak Temple Complex comprises a vast mix of decayed temples, chapels, pylons, and other buildings. Building at the complex began in the reign of Sesostris I in the Middle Kingdom and continued into the Ptolemaic period, although most of the extant buildings date from the New Kingdom. The area around Karnak was the ancient Egyptian Ipet-isut ("The Most Selected of Places") and the main place of worship of the eighteenth dynasty Theban Triad with the god Amun as its head. It is part of the monumental city of Thebes. The Karnak complex takes its name from the nearby, and partly surrounded, modern village of el-Karnak, some 2.5 km north of Luxor.

The history of the Karnak complex is largely the history of Thebes and its changing role in the culture. Religious centers varied by region and with the establishment of the current capital of the unified culture that changed several times. The city of Thebes does not appear to have been of great significance before the Eleventh Dynasty and previous temple building here would have been relatively small, with shrines being dedicated to the early deities of Thebes, the Earth goddess Mut and Montu. Early building was destroyed by invaders. The earliest known artifact found in the area of the temple is a small, eight-sided temple from the Eleventh Dynasty, which mentions Amun-Re. Amun (sometimes called Amen) was long the local tutelary deity of Thebes. He was identified with the Ram and the Goose. The Egyptian meaning of Amen is, "hidden" or, the "hidden god".

Major construction work in the Precinct of Amun-Re took place during the Eighteenth dynasty when Thebes became the capital of the unified Ancient Egypt.

Thutmose I erected an enclosure wall connecting the Fourth and Fifth pylons, which comprise the earliest part of the temple still standing in situ. Construction of the Hypostyle Hall also may have begun during the eighteenth dynasty, although most new building was undertaken under Seti I and Ramesses II.

Almost every pharaoh of that dynasty has added something to the temple site. Merenptah commemorated his victories over the Sea Peoples on the walls of the Cachette Court, the start of the processional route to the Luxor Temple.

Hatshepsut had monuments constructed and also restored the original Precinct of Mut, the ancient great goddess of Egypt, that had been ravaged by the foreign rulers during the Hyksos occupation. She had twin obelisks, at the time the tallest in the world, erected at the entrance to the temple. One still stands, as the tallest surviving ancient obelisk on Earth; the other has broken in two and toppled. Another of her projects at the site, Karnak's Red Chapel, or Chapelle Rouge, was intended as a barque shrine and originally, may have stood between her two obelisks. She later ordered the construction of two more obelisks to celebrate her sixteenth year as pharaoh; one of the obelisks broke during construction, and thus, a third was constructed to replace it. The broken obelisk was left at its quarrying site in Aswan, where it still remains. Known as The Unfinished Obelisk, it demonstrates how obelisks were quarried.[6]

The last major change to Precinct of Amun-Re's layout was the addition of the first pylon and the massive enclosure walls that surround the whole Precinct, both constructed by Nectanebo I.

In 323 AD, Constantine the Great recognised the Christian religion, and in 356 Constantius II ordered the closing of pagan temples throughout the empire. Karnak was by this time mostly abandoned, and Christian churches were founded amongst the ruins, the most famous example of this is the reuse of the Festival Hall of Thutmose III's central hall, where painted decorations of saints and Coptic inscriptions can still be seen.

Source: Wikipedia

11. Karnak Temple, Luxor, Egypt
of the
"..The Most Selected of Places..." -  ancient Egyptian saying about Karnak