A northern 75km

Take in some of London's cyclists' favourite training roads north of the city. After a couple of short, sharp shocks on the way out (yes, we are taking you up Swain's Lane!), you'll appreciate the gently rolling hills and quiet lanes. Have a coffee stop half-way at Hertford, perhaps, and then head back in to central London, and maybe a pint and some lunch at the picturesque Flask pub in Highgate.