Much like capes and headlands on Earth face the sea on three sides, “Promontorium Heraclides” is surrounded by lava plains on the Moon!
The Moon was a volcanically active place. The dark regions — the Maria —were once seas filled with lava, now solidified to form lava plains. The mountainous cape of Promontorium Heraclides surrounded by lava plains is actually part of a raised crater rim!
The flowing lava during the time of active volcanism breached the lower rim walls and drowned it, leaving behind a cape/headland like feature on the Moon! The previously covered lava-flooded Letronne crater also has headland features.
The Soviet lunar probe Luna 17 landed near Promontorium Heraclides in 1970, about 30 km away. It carried with it the first ever robotic lunar rover called Lunokhod 1. The rover traveled more than 10 km in the lava plain.