A Thames sailing barge

is a type of commercial sailing boat

once common on the East Coast of Britain.

The flat-bottomed barges with a shallow draught and leeboards,

were perfectly adapted to the Thames Estuary,

with its shallow waters and narrow tributary rivers.

The larger barges were seaworthy vessels,

and were the largest sailing vessel to be handled by just two men.

The average size was about 120 tons and they carried

4,200 square feet (390 m2) of canvas sail in six working sails.