Our route was just a tiny bit over 17 miles, and we spent 1 hour 25 mins cycling and about another 20 mins or so in three short breaks at about 4.5, 10 and 15 miles. I'd say the route out through Histon and Cottenham is a *bit* fast and narrow for cycling on in places if you're not confident, but there is a cycle path on the pavement on the fastest bit between Histon and Cottenham.

Train back is £4.10 each.