A restored 12th-century Crusader castle surrounded by a 10m-wide dry moat is located just inside the entrance to Byblos' atmospheric archaeological site, which incorporates Neolithic, Chalcolithic, Greek and Roman ruins. There are panoramic views over the ruins and harbour from the castle's rooftop and crenellated towers – be sure to climb the stone staircases to the top of the donjon (fortified central tower) to appreciate these. Inside, there's a small museum and a room with information panels outlining the city's history.
After exploring the castle, backtrack to the site entrance and turn left to explore the ruins, which include the remains of city ramparts dating from the 3rd and 2nd millennium BC; three temples; and a Roman theatre overlooking the sea. In the Roman period (64 BC–395 AD), the streets here were lined with colonnades and sculptures adorned most public places. Interestingly, the layout wasn't according to the usual Roman grid, instead being adapted to the existing monuments on the site.
The L-shaped Temple of Resheph dates from the 3rd millennium BC, and is thought to have been burned down during the Amorite invasions. More recent (early 2nd century BC) are the remains of the Obelisk Temple ; the 1500 gold-covered votive offerings in the shape of human figures discovered here in the 20th century are now displayed at Beirut’s National Museum.
The site's oldest temple, the Temple of Baalat Gebal (the Mistress of Byblos), dates back to the 4th century BC. This was the largest and most important temple constructed at Byblos, dedicated to Aphrodite during the Roman period, and was rebuilt a number of times over its two-millennia long survival. Many temple findings, including alabaster vase fragments inscribed with the names of Old Kingdom pharaohs, are today also housed in the National Museum. The six standing columns approaching the temple are the vestiges of a Roman colonnaded street dating from c 300 AD.
West of the Temple of Baalat Gebal is the Roman theatre , a reconstruction that’s one-third the size of the original. This is situated near the cliff edge and has great views across the sea. Behind this are nine royal tombs , cut in vertical shafts deep into the rock in the 2nd millennium BC. Some of the sarcophagi found here are now housed in the National Museum, including that of King Hiram, whose sarcophagus has one of the earliest Phoenician alphabet inscriptions in the world. His grave shaft also is inscribed, this time with the eerie phrase, ‘Warning here. Thy death is below.’
Other remains include the King’s Well , a spring that supplied the city with water until the end of the Hellenistic era (and where, according to legend, Isis sat weeping on her search for Osiris); and remnants of Neolithic (5th century BC) and Chalcolithic (4th century BC) enclosures, houses and huts.