They start and finish at O.
On they way, they have to collect a ticket from each of the points A, B, C, D, E, F and G, though not necessarily in that order.
The side of each small square is 60 metres. Points A, D, E and F divide the sides of the small squares in the ratio 2:1. What is the shortest route?
The shortest route is 700 metres, collecting the tickets in the order OACBGFDEO. Return to the centre line after visiting A. After D, return to the centre line, go down past E and back to O along the bottom line.