A torch on his head, Jason Sandy scours the nighttime London foreshores of the Thames river, searching for objects that could offer a glimpse of life in the British capital hundreds of years ago.
As the occasional party boat passes by, its music blasting and lights flashing, the 42-year-old architect only has a few hours while the tide is low to make his finds.
Mudlarking is believed to trace its origins to the 18th and 19th century, when scavengers searched the Thames' shores for items to sell. These days, history and archaeology fans are the ones hoping to find old relics such as coins, ceramics, artefacts or everyday items from across centuries.
They wait for the low tide and then scour specific areas of exposed shores.