Weathertop is a dark and dangerous place.
It was once a great watchtower, one of many built by the Numenorians when they first began to settle in Middle Earth. These citadels were stationed in several key locations. Each housed one of the Palantiri, the seven seeing stones that allowed the Numenorians to keep in communication with each other across the kingdoms.
During the modern events of The Lord of the Rings series, the very first struggles for the One Ring occurred at Weathertop. When Gandalf encountered the nine Ringwraiths on that high summit, a fiery battle ensued, leaving the hilltop scorched. At sunrise the following day, the power of the Ringwraiths waned, allowing Gandalf to flee to the hills. Gandalf hoped to lure away the Ringwraiths, but not all pursued him.
Aragorn and Frodo witnessed the battle from a few miles away, but they did not know what it was at the time. They beheld it as repeating flashes of light that illuminated the distant dark. Aragorn described it as being “like lightning that leaps up from the hilltop.”
Three days later, the Hobbits arrived at Weathertop where they were ambushed by the Witch King and the remaining Ringwraiths. Aragorn managed to come to their rescue but was too late to prevent the Witch King from stabbing Frodo. The Ringwraiths escaped and Frodo was left poisoned by the Witch King's Morgul Blade.
