This is a score event around the streets of Marston and Headington, starting on the grass just behind OXSRAD https://www.oxsrad.org/
To find it in MapRun, open the app and then Select Event > UK > Thames Valley > Oxford Street Series >MarstonHeadingtonStreetO.
OXSRAD is located just off the A40 Marston turnoff, on Marsh Lane. Grid reference SP532084.
Parking is available at OXSRAD for a modest fee (note that free parking in the area is almost non-existent due to the proximity of the JR Hospital)
Standard Oxford Street-O rules apply: 10 points for each control numbered 10-19, 20 points for each control numbered 20-29, and 30 points for the controls numbered 30-39. Visit as many controls as you can in 60 minutes. There is a penalty of 20 points for each minute (or part thereof) you are late back to the start. (Note this is twice what the penalty has been in the past.)
The controls are almost exclusively street signs, and are detailed on the back of the map.
Download the map in PDF: https://www.dropbox.com/s/zm1qy4e8xuxwqsx/MarstonHeadingtonStreetO-withcds.pdf?dl=0