Police have released CCTV images in a fresh appeal to trace a trainee nurse from Bristol.
Anna Lewis, 27, who lives in Fishponds, was last seen last seen leaving her work placement at Southmead Hospital on Thursday 13 April.
Avon and Somerset Police said her disappearance was "out of character".
A spokesman said Ms Lewis was known to go on camping trips without telling others but had never gone missing for such a long time before.
The police spokesman added they were "growing concerned for her welfare".
Ms Lewis was reported missing on Friday by her family, who do not live locally.
She is described as white, about 5ft 5in tall, of slim build, with brown eyes and long dark brown hair; which she tends to wear in a low ponytail.
Police said she tended to wear jeans or walking trousers, hiking boots and loose jumpers.