Now, imagine a city as bustling as Calcutta, India. Notorious for its slums and a population of 5 million. Imagine losing a child in that city!
That's what happened to a young Indian boy, Saroo. He was five years old, fell asleep on a bench, only to wake up realizing his older brother was no where in sight. When he awoke, he jumped on the train in front of him assuming he'd find his brother on board. After a 14 hour train ride, and no luck finding his brother, he realized he was lost.
He ended up getting adopted by an Australian family and raised there. With access to the internet and Google Maps, he was able to start tracking down his family in an attempt to reunite with them. He used Google maps and his "vivid" memory to start looking at cities that seemed to fit where he grew up.
Long story short, he found the city and was able to successfully track down his mother. The story is well worth the read. Follow the source jump below.
Source: BBC