By P Karunakharan
BBC Tamil service, Colombo
The Sri Lankan military has been deployed to evacuate tourists hit by a deadly aerial menace at the world famous rock fortress at Sigiriya.
The site is famous for its beautiful frescoes
They have helped take dozens of people to hospital in recent days after they were stung by an angry swarm of wasps.
Police say that the prevailing hot weather, combined with the noise made by crowds of visitors, could have roused the normally peaceful wasps.
Hundreds of thousands of visitors each year visit the World Heritage Site.
Some people believe the wasps are the reincarnation of troops of King Kasyapa, who built the fortress in the year 475 AD.
Wasp attacks are not uncommon at the site, 150km (100 miles) north-east of Colombo. The fortress is regarded as one of the wonders of the world.
In 2004, Buddhist monks lit lamps and incense sticks to pacify the insects, when they were believed to have been disturbed by children throwing stones at a nest.
Police say that at least 100 people have been taken to hospital in the latest attacks - while several others received first aid - after they were stung at the foot of the 200-metre-high fortress.
The frescoes at Sigiriya - similar to ones of Ajantha in India - are renowned for their age and beauty.
Almost equally legendary are its various swarms of wasps, who sometimes have an uneasy co-existence with equally large swarms of tourists.
The authorities say that they are reluctant to fumigate or smoke out the insects, for fear of damaging the ancient frescoes and its most famous exhibit, three women known as the Sigiriya maidens.