Mudlarks Andy Johansen and Ian Smith dig holes as they look for objects on the banks of the River Thames in London. They sometimes find 2,000-year-old artifacts. (Neil Hall/Reuters)

A flashlight on his head, Jason Sandy searches the nighttime shores of London’s Thames River, looking 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.

For the last five years, Sandy has made a hobby of mudlarking, thoroughly scanning and searching the river banks for historical artifacts. Some of his finds are so rare they are displayed in museums.

“Over 2,000 years of time, everything has been thrown into the Thames, accidentally lost,” he said. (The river’s name is pronounced TEMZ.)

“It’s really the thrill of almost like time traveling and knowing that the last person to touch this was from that time period,” he added, describing the feeling of making a find.

Some of the objects recently uncovered — and not yet cleaned — by mudlarks Andy Johansen and Ian Smith. (Neil Hall/Reuters)

Sandy, originally from Chicago, has found numerous artifacts, including a comb from England’s 16th-century Tudor era; a 19th-century toothbrush; and a Roman women’s hair pin that the Museum of London dated to the year A.D. 43.

Mudlarking is believed to trace its origins to the 18th and 19th centuries, when scavengers searched the Thames’s shores for items to sell. These days, history and archaeology fans are the ones hoping to find old relics such as coins, ceramics, artifacts or everyday items from across the centuries.

They wait for the low tide and then scour specific areas of the foreshore, the part of the shore that is covered with water during high tide.

“If you’re in a field you could be out all day long. With the river you’re restricted to about two or three hours,” mudlark Nick Stevens said. “Unlike fishing, where there’s one of 10 fish that you’re likely to catch, with mudlarking there is an infinite amount of variety in terms of what you could find.”

While many just use the naked eye for their searches, others rely on metal detectors for which a permit from the Port of London Authority is needed. Digging also requires consent.

The Society of Thames Mudlarks counts just a few dozen members, who have the necessary licenses and can access restricted areas along the river.

A collection of Tudor-era coins excavated from the River Thames by mudlark Jason Sandy. (Neil Hall/Reuters)

Collaborating with the Museum of London, the mudlarks record their finds with the government-funded Portable Antiquities Scheme. Any item over 300 years old must be recorded.

“It’s quite exciting to go down to a part of London that is only accessible for a very short amount of time,” Sandy said.

“Thousands of years of London’s history is still waiting to be discovered there on the Thames foreshore.”