The company identified the find as a "removals" car, meant for moving property from a person's old home to a new residence.
"The wooden removals truck is thought to be around one hundred years old," consultant archaeologist Femke Martens said in the LNER news release. "It's a mystery as to how the carriage came to be in Antwerp, and unfortunately there's very little left of the relic as it disintegrated while being excavated."
LNER researchers said the car appears to be the very first model of a removals car, and they were used only briefly around 1930 before the company replaced them with updated blue models.
The company said researchers still haven't determined how the car came to be buried 500 miles from LNER's British headquarters.
"This curious find has certainly generated lots of interest and we are delighted the team from the Urban Archaeology department of the City of Antwerp have helped shed more light on the discovery," LNER spokesman Stuart Thomas said. "We're fascinated by LNER's history, and we'd like to thank the team for their help in unearthing more information about LNER's proud past."
