Lincolnshire Police are appealing for information after a man in his 20s flashed a woman on Yarborough Road in Lincoln.
The woman was walking near to the allotments at just after 7am on January 4 when she was approached by a man who exposed himself.
Police have described the man as being in his mid 20s, with short, shaved dark hair, thought to be a number two cut.
The flasher was wearing thin rimmed glasses which were light, possibly silver, blue jeans, dark trainers and a long sleeved light blue top with a diagonal white band across the front.
Police believe that the offender left the scene via the steps leading down to North Parade.
Anyone who thinks they recognise this description is urged to call 101 with incident reference number 58 of January 4.