How dangerous are the wasps on Sigiriya rock really

Real but manageable. Sigiriya rock has wild giant hornet nests on the cliff face, and over the years there have been serious incidents where swarms attacked visitors and the rock was temporarily closed. The site now has wire-mesh "wasp screens" installed near known nest locations and trained staff who pause visitors when wasps are active. Triggers are vibrations, loud noise, perfume/cologne, and sudden movements. Rules: do NOT shout, run, slam the metal staircases or use strong fragrances. If a swarm goes off, the official advice is to stop, stay low, cover head and neck with your hands or a sarong, and stay still until it passes; do not flail or swat. Site staff carry alarms and will direct everyone calmly. Climbing early morning (around 7am opening) is the safest window as wasps are less active in cool air.