He found the lost city after spotting the ruins (seen in the picture below) from a helicopter and decided to work out what it was. He had no idea how lucky he was, the ruins are only visible when the spring tides are unusually low.
After Allan first spotted the ruins from a helicopter, it took him almost 3 years to pinpoint its exact location and on March 21 on this year he discovered something that could probably change the way we think about African history.
Since Allan Sutten discovered the lost ancient city, Felix Chami, a professor from Dar es Salaam University has been to the site and says it could change our understanding of history.
Reseachers are still investigating the site that is the size of a small city so not much more information can be found about Tanzania’s “lost city”.