In the chalk hills of northeast Hertfordshire you are walking in the 'champion' country – that is how it was described by contemporaries such as the early Hertfordshire historian Sir Henry Chauncey, writing in the late 17th century. The word, a corruption of the French 'champagne' or country (not the sparkling wine), describes classic, Midland, open-field farming country. Here, fields were farmed in common, with holdings divided up into strips within great open fields, usually two, three or four surrounding a village. Every farmer, from the peasant to the yeoman farmer and up to the great landowner, had a share of the best and worst land. In addition there were areas of common grazing, wood and hay meadows.

Enclosure acts

This system had immense benefits for the small farmer, but none for the more progressive and larger farmers who, over the centuries, tried to enclose the open fields for more efficient, centralised farming. This area of Hertfordshire held out longest. Kelshall's open fields were enclosed, following a private Act of Parliament, in 1795; Therfield's became enclosed as late as 1849. You can see the effects of efficiency now – vast arable fields with very few hedges descend northwards from the villages on the ridge to the ancient Icknield Way at the foot of the chalk downs, often their parish boundary. However, the area of this walk is in the more intimate fields south of the villages, where the countryside is criss-crossed by ancient and attractively hedged, pre-enclosure, green lanes such as Kelshall Lane and Duck's Green, winding amid the smaller, arable fields.

Village scenes

Therfield has a fine triangular village green with The Fox and Duck pub on its eastern side. The church was entirely rebuilt in 1878 due to subsidence. The rebuilding re-used many items from the previous medieval church. These include piscinae, the stone basins which were usually close to the altar in a pre-Reformation church, some roof bosses and monuments, the best being that to Francis Turner, who died in 1677. The Old Rectory, southeast of the church, is also of interest. It has a rendered, 15th-century wing and a circular stair turret. The rest of the building is a red-brick, Georgian rebuild from 1767. To the west of the church are the earthworks of a motte-and-bailey castle. This was started by the Abbot of Ramsey during the civil wars of Stephen's reign. Kelshall, the smaller village, retains its mainly 15th-century church, although it was extensively restored in 1870. Entry is through the medieval oak door and there are fragments of medieval glass. The lower part of the chancel screen also survives.

From Therfield village green walk down Church Lane and into the parish churchyard. Go through a gap in the railings to the south of the south porch and bear left on to a green lane, with the vicarage garden on the left and a field on the right. At a footpath post keep straight on along a grassy margin at the left of a field, then go across a field to a kissing gate. Cross pasture to another kissing gate, go through this and turn right on to a green lane, Duck's Green. Ignoring footpaths to right and left, the track bears left, now following the parish boundary. Where the path meets a track, turn right on to a green lane.

Follow this green lane, which soon turns right, climbing gently between ancient hedges. At a track junction go left and continue climbing, passing a footpath junction before reaching the crest of the hill. Ignore a track turning left – carry straight on along a loosely metalled track.

Further on turn right on to the bridleway, with a fence and paddocks to the left, arable land to your right. This becomes a track through arable land. At a bridleway post, where the hedge reappears on your right, turn right on to a green lane, soon hedged only on the left. At a post-and-railed sheep enclosure go left. Then, through a gate, turn left to another gate on to a lane and cross to the church lychgate.

Visit the St Faith's Church, entering through its original, heavy, 15th-century door. Leave the churchyard from behind the chancel on to a path between a fence and walls, signposted 'Hertfordshire Way'. At the lane turn left. At the road junction jink right then left to walk past the telephone box and the village hall, dated 1895.

Continue past Fox Hall Farm and a pond. Turn right at a footpath sign, just before a thatched cottage, on to a track initially between hedges, then alongside a patchy hedge. At the end of the field go through a kissing gate and, just before the footbridge, turn left. After a few paces, with the ditch on your right, turn right at a footpath sign. At the track go left to walk past the tall water tower. At the road turn right and follow it past Tuthill Court and some Victorian estate cottages. Turn right past Bell House into Pedlars Lane, which winds back to Therfield village green.