3 Options;
Please note I have had to change the second route as the path between Coopers Lane Rd and the Ridgeway at Holly Hill Farm is impassable (very overgrown... no avoiding nettle stings and bramble scratches sadly)
Hilly Fields, Crews Hill & Whitewebbs Loop | 9.03km / 5.61ml run
Car Park, Hilly Fields, Crews Hill Golf Club, Garden Centres, Theobalds Park Rd, Flash Lane, Bridleway to WW Lane, King & Tinker, Stile, Trail past Beaver enclosure, Cafe
https://gb.mapometer.com/running/route_5456164
Hilly Fields, Crews Hill, Whitewebbs and Forty Hall | 11.73km / 7.29ml run
Car Park, Hilly Fields, Crews Hill Golf Club, Garden Centres, Theobalds Park Rd, Flash Lane, Bridleway to WW Lane, King & Tinker, Spurs, Maidens Bridge, Rose Garden, Cafe
https://gb.mapometer.com/running/route_5457793
St John's Sch, Hook Lane & Vineyards | 19.57km / 12.16ml run
Car Park, Hilly Fields, Strayfield Rd, Rectory Rd, Ridgeway, Footpath at St John's Prep, Coopers Lane Rd Bridleway, Hook Lane, Northaw, Vineyards, Cuffley Tennis Centre, Cross Roads, Burnt Farm Ride, Jollye's, Flash Lane, New River Path, Cafe