What is the deepest valley in the world?
Kali Gandaki Gorge
The Kali Gandaki Gorge or Andha Galchi is the gorge of the Kali Gandaki (or Gandaki River) in the Himalayas in Nepal. The Kali Gandaki gorge is the deepest gorge in the world, being lower than Annapurna I which bounds it at one point.
Woodingdean Water Well
The Woodingdean Water Well is the deepest hand-dug well in the world, at 390 metres (1285 feet) deep. It was dug to provide water for a workhouse. Work on the well started in 1858, and was finished four years later, on March 16, 1862. It is located just outside of Nuffield Hospital, in Woodingdean, UK.