On August 1, Maks Czuperski, director of the @DFRLab, challenged the #DigitalSherlocks to use their geolocation skills to identify where he was, based solely on a photo taken in the area. In 17 minutes, Rafal Zabinski (@RafalZabinski) succeeded in identifying the location of the photo as Bangkok, Thailand. The following account from Rafal on how he geolocated Maks provides some insight into the tools and methods of our #DigitalSherlocks.

On August 1 I was scrolling through my Twitter feed when I came across a tweet from Maks Czuperski.

To my excitement, it was another geolocation challenge. I’ve been following these for some time but I’ve never actually solved any, so I was really eager to try again. I downloaded the image and got down to work.

At first I studied the photograph in search of clues.

The biggest clue was the river. It had a very characteristic “S” shape, and from the beginning I knew this shape would be a crucial to my investigation. I could also see some kind of vessels on the water. Together with highly industrialized areas on both sides of the river, this gave me the impression of a really big city.

I also picked up two details that I thought might be useful later. First of all, there was a small lake with a white patch of ground next to it. The second detail was that there was three white buildings located next to each other. The altitude from which the photo was taken suggested that it was taken either during takeoff or landing. So the location I was looking for must be somewhere next to an airport.

Based on previous tweets, I knew Maks was traveling around Asia, so I thought it was a pretty safe bet that he was still somewhere in the area.

To sum up, at this point I was looking for an airport, next to a curvy river, somewhere in Asia. Good luck to me!

My first approach was ambitious. I decided that I would find the flight that Maks was on. Since his last tweet was from Kuala Lumpur and I knew exactly when the tweet was posted, I thought that maybe I could figure out which flight he took and this could lead me to the location. Well this plan went out of the window fairly quickly when I realized that the only way this could work is if I knew for sure that the photo was posted then and there, seconds after it was taken. But what if Maks had posted the photo, let’s say, from a hotel, hours after arriving at the new location? The time frame was simply too large.

So I chose a much simpler approach. I decided I would just Google all the big airports in Asia and see if maybe one of them is in close proximity to a curvy river. On Wikipedia I found a list of the busiest airports in Asia and I just start Googling each of them on Google Earth.

Suvarnabhumi Airport in Bangkok was ninth on the list. When I saw the shape of the river next to the airport I knew I hit the jackpot. It took me a few seconds to find the small lake and the three white buildings that I spotted in the original photo.

At this point there was no doubt that Maks was in Bangkok.