The Cheltenham man was arrested on suspicion of rape and remains in custody.
It follows patrols that were carried out in part of Pittville Park this morning after reports of sexual assault.
Police were called to the scene after learning that a woman had been sexually assaulted around 5 a.m.
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Officers continue to investigate the park and the stage warden will remain in place until this is complete.
The woman is now being taken care of by specialized agents and investigations are underway at the moment.
A passing witness told us that there is a “significant police presence in the park this morning” and that “the area south of the bridge is cordoned off”.
They also told us that “several police vehicles are present” and that “officers are also searching an area through the pitch and putt”.
If anyone has any information, they are asked to fill out a form by clicking here and citing Incident 85 of June 12.
Information can also be submitted by calling 101 and quoting the same incident number.