Ho Klong was a drum tower about 55 meters high, consisting of three stories, with each a drum. The structure stood in the centre of the city of Ayutthaya on Talaeng Kaeng Road (Four Ways Road). Its roof was arched and painted red. The drums were beaten to warn the population in case of fire, signal the approach of enemies or summon people for meetings.
Each storey had its function. Phra Thiwaratri, the drum on the first storey, was beaten to mark noon and to call up people for a public meeting at dusk according to the customs of the city.
When a fire was spotted, the drum called Phra Maha Rangap-phloeng on the middle storey was sounded. If a fire occurred outside the city, Phra Maha Rangap-phloeng was beaten three times. If the fire occurred at the foot of the city walls or in the city itself, the drum was beaten until the fire was extinguished.
The highest storey was used to watch the approaching enemy, on which the drum called Phra Maha Ruek was beaten.