Italy
The Kollur Mine was a series of gravel-clay pits on the south bank of the Krishna River in the state of Andhra Pradesh, India. It has produced many large diamonds, known as Golconda diamonds, several of which are or have been a part of crown jewels of various empires. The mine was established in the
early 17th century and operated until the mid-19th century.
Listen to the audio guide for Kollur Mine Free on WIP — starts by itself when you arrive, even with the screen off