What is "heliodurus"

Heliodurus (or Heliodorus, ) was a Greek ambassador sent to the court of King Bhagabhadra by Antialcidas (Greek King of Taxila) in 113 B.C. He is known for building a pillar called the "Khamb Baba" or "Heliodurus Pillar" which still exists in Vidisha, India near Bhopal, India.

Heliodurus converted to Hinduism and built a pillar which states the following (translation from the Journal of the Royal Asiatic Society - London: JRAS, Pub., 1909, pp. 1053–54.) in ancient Brahmi text:

The first modern-time Western observation of the column was by Major General Alexander Cunningham K.B.E in 1877. However, Sir Cunningham did not notice the inscriptions on the pillar, which were later discovered in 1901 by another British archaeologist.

Even most local people are unaware of the existence and the historical significance of this pillar.