The woman was declared missing from a party touring the Eldgja volcanic region in south Iceland after getting off the party's bus to freshen up, the Daily Mail reported.
She hopped off the bus briefly, but had also changed her clothes - and her fellow travellers did not recognise her when she climbed back on again to continue the party's journey.
Soon the search began for a woman described as Asian, around 160 cm, in dark clothing and speaking English well.
When the details of the missing person were issued, the woman reportedly didn't recognise her own description and unwittingly joined the search party for herself.
After a night-long operation involving around 50 people, the 'missing woman' eventually realised she was the source of the search and informed police.
The search began on Saturday, but was called off at around 3 AM (local time) on Sunday morning when the woman realised she was the subject of the frantic efforts.