Here's a map of the F12/10.  the race HQ is usually the Grovebury Road scout hut, but sometimes Billington village hall is used.

COURSE F12/10 - 10 MILES (1999) Start Sheet text
START on A505, 182 yards east of Grovebury Road RAB opposite a RAB sign on the
other side of the road. Proceed eastwards along A505, straight on at Billington
RAB to RAB junction with A5 to:-
TURN (5.2 miles) by taking 3rd. exit out of RAB and retrace westwards along A505,
straight on at Billington RAB to:-
FINISH on A505, 126 yards east of (i.e.,before) bridge over the A505, some 680 yards east
of the start.
Police Area : Bedfordshire
LOCAL REGULATIONS No. 1 and 3 (page 13) apply.

{mosmap width='500'|height='400'|kml=''|zoomType='Large'|zoomNew='0'|mapType='Map'|showMaptype='1'|
overview='0'|text='sv DWO'|tooltip='DWO'|marker='1'|align='center'}