I'd say they they are both about 20 miles. the Tuesday ride goes over to the coast, up Torrey Pines Rd and down to La Jolla Shores, up Calle de Oro/Prestwick and back to Sorrento Valley. The thursday ride goes up El Camino Real to San Dieguito Rd up to El Apajo and back. I was told that these were the regular routes (I have done each one once with the group) so this may not be exact. This may not be the mileage that you are looking for but I will assure you that you will get a workout. They are mostly current or ex-racers and take this ride very seriously (translation they crushed my puny soul!)