This in my opinion is the best route for a Rivington ride incorporating San Marino:
https://www.strava.com/activities/361241856
Ride from Rivington upto Rivington Moor, along George’s Lane then up the path towards Two Lads hill, then the access road to Winter Hill radio towers. San Marino descent, pass Belmont resr then Delph resr. Follow Witton Weavers Way all the way to Tockholes, then up to Darwen Moor then some singletrack to the Jubilee Tower. Long descent down to & through Roddlesworth Woods. Of cause you could miss out Darwen Moor but while your over in Tockholes it would be a shame to miss it out as it is great. Then you go over to Brinscall, slight downhill grade all the way to Healey Nab. Alternatively could go up and over Wheelton Moor for another climb with good views and good descent into White Coppice. Could do the red-graded trail at Healey Nab or just ride past it if lacking on time. Alternatively you could ride the flat route alongside Yarrow reservoir. Then its through Anglezarke short climb gradual descent passed the reservoirs to Rivington and then Liverpool Castle ruins & back to cars.
Great route about 47k and takes about 3 hours going at a moderate pace. I do this route at least a few times a year, if I’m riding from Rivington I always tend to do this. It makes a much better day out than just riding back up San Marino it actually feels like you’re going to more different places. I don’t see the point in riding back up San Marino when there’s so much good riding in the moors behind Winter Hill. If anyone is up for a ride on this route let me know.