In the thirteenth century BCE, the Egyptian pharaoh Ramesses II left three reliefs on the south bank of the Nahr al-Kalb, north of Beyrut, which commemorated the northern campaigns that culminated in the battle of Kadesh (1274). Several centuries later, the Assyrian king Esarhaddon conquered Egypt, and chose to put a memorial opposite the relief of Ramesses. Ever since, armies have left inscription at the Nahr al-Kalb, a custom known to Herodotus (more).
All in all, there are twenty-two inscriptions and two monuments, with texts in seven languages (Egyptian, Akkadian, Greek, Latin, Arabic, French, and English). Together, they give a nice overview of Lebanese history.