Detectives have released a new e-fit from descriptions after a report of rape was made in June 2024.
Enquiries have established the incident happened around 4-5am off Deansgate road in the city centre on Thursday, August 17 2023.
No arrests have been made at this stage, but the investigation is continuing.
Detective Constable Rowan said: “We are now able to ask for the help of the public to try to identify the person involved in this incident.
“After obtaining witness statements and descriptions, we have managed to produce an e-fit that should hopefully help in that process.
“Since we were informed of the incident recently, we have ensured the relevant support has been provided to the woman whilst ensuring we can move swiftly to see if we can identify the person responsible.
“In the background, we are continuing with our enquiries despite the time passed since the incident took place and remain committed on tackling serious sexual offences.”
Anyone with information is asked to call police on 101 quoting incident 2435 of 27/06/2024. Alternatively, details can be passed on anonymously to Crimestoppers on 0800 555 111.