I can get so wound up about the rights and wrongs of cycling in the city that it's easy to forget that bikes are fun as well. So head for the hills!

My favourite city escape is mountain-biking in the Chilterns. I used to catch trains out to the Cotswolds, but the Chilterns are easier to reach from Oxford and offer better cycling.

From where the M40 bisects the hills, head south for the best on- and off-road routes.

All summer, even at the height of the floods, the Chilterns remained dry.

It's still warm, and now the leaves are turning, it's stunning.

Christmas Common, about three miles south of the M40 junction 6 at Lewknor, is a good base. It's easy to reach by car or bus. I even know a couple of keenies who cycle all the way from Oxford.

It's "only" 15 miles, but there and back on the road - plus a 20-mile off-road circuit when you get there - is more than enough for most mortals.

By bus, take the Oxford Tube to Lewknor Turn (about £5 return). Although five or six bikes would fit in their capacious holds, the maximum number allowed is two.

Increasingly, the bus already has a bike or two on board, but I've never had to wait for more than two buses to get mine on. Bikes travel free.

From Lewknor, cycle three miles into Watlington and turn right before the shops. Go to the top of the hill - it's a steep two-mile climb to Christmas Common.

It's high up and at this time of year, it's a few degrees cooler than in Watlington, at the bottom of the hill.

By car, take the B480 from Cowley to Watlington. Turn left at the signs for the M40 and then right after the shops. Park at the top of the hill.

The ride starts with some downhill and flat sections by way of a warm-up before the hard work starts. Cycle north from Christmas Common, with the radio beacon on your right, and take the bridleway on your left, down a steep chalky hill, marked the Oxfordshire Way on maps.

Turn left and follow Icknield Way and then Swan's Way along the bottom of the hills. These ancient rights of way are wide and easy riding - you could easily make a day out of it with a family picnic.

At Sliding Hill, turn left and head south over Ewelme Downs to Harcourt Hill. In winter, these tracks are a brake-clogging quagmire, but for the last six months, the ride has been a lot quicker than usual.

Pick up the Chiltern Way as it heads through the woods north of Nettlebed, and head for Stonor.

Make sure you've got plenty of water and energy bars as there isn't a shop or pub for miles around.

The valley sides are steep but worth the thigh-ache getting up for the long downhill blasts.

When you've had enough, the best way back is the roughly maintained lane from just west of Stonor Park through Queen's Wood to Christmas Common. Once you see the radio beacon, you're nearly there.

But make sure you have reserves for that last climb - it can feel like it'll never end. If you're bussing, you can jet-wash your steed at the garage in Watlington to improve your welcome aboard the Oxford Tube.