It was reported just after 7pm on the night of Sunday 13 August 2017.
The victim was walking along the lane near kennels at the back of the football field when a man walked past her and touched her sexually through her clothing.
Police are appealing to anyone who was in the area at the time, and in particular are keen to speak to a man who stopped to talk to the victim before the incident happened.
The man and anyone who was in the Wooden Hill Lane area of Northallerton between 6.30pm and 7.15pm on Sunday 13 August, is asked to contact North Yorkshire Police on 101, select option 2 and ask for Northallerton Serious Crime Team. Or email firstname.lastname@example.org
If you wish to remain anonymous, you can pass information to Crimestoppers on 0800 555 111.
Please quote reference number 12170143436 when passing on information.
A 19-year-old man has been charged with sexual assault and appeared at Harrogate Magistrates’ Court on 15 August 2017. He has been remanded in custody to appear at Teesside Crown Court on 11 September 2017.