North Wolds' Geology

Caistor's origins are Roman, its name Castra meaning camp or fortification, and small fragments of the original encircling wall still remain in the vicinity of the church. Ermine Street passed close by, and a short hillside track joined Caistor to the important north-south route from the Humber to the Roman fort of Banovallum (modern-day Horncastle). Caistor town centre is dominated by several impressive Georgian houses, but sadly few from earlier times, since a disastrous fire in 1861 burnt down most of the town.

Caistor and Nettleton sit at the foot of the sharp western escarpment of the Lincolnshire Wolds, a modest but undulating series of chalk uplands in the county's north east corner, which form the highest land on England's eastern seaboard between Yorkshire and Kent. The high point is Normanby Top, just off the walk, at the dizzying height of 550ft (168m)!

The main rocks of the Wolds - chalk, limestone and sandstone - were laid down during the Cretaceous era around 65 million to 135 million years ago. Overlying sands and gravels came later, during the ice ages of the Pleistocene era, around 1.8 million years ago. Although dominated by a thick band of chalk, the western fringes of the Wolds have deposits of ironstone which was mined (and quarried opencast) during the last century near Nettleton Top. The ore was taken down the hillside and transported by rail to Scunthorpe for smelting. The machinery has disappeared, but the mounds and scars are still evident today.

The high chalk Wolds have poor, thin soils, and are mainly, but not exclusively, grazed by sheep. However, in the south of the Wolds the chalk is covered with deposits of boulder clay, gravel and sand, which give rise to better agricultural soils. Although some villages even had their own brickworks, the chalk has also been quarried for building stone.

The Wolds were designated an Area of Outstanding Natural Beauty in 1973. The Lincolnshire Wolds Countryside Service aims to promote the landscape and its conservation, and improve opportunities for quiet recreation. They produce a range of useful leaflets and a regular guide to what's happening in the region (called Wolds News), as well as organising guided walks and events. To find out more contact the Countryside Service at Navigation Warehouse, Riverhead Road in Louth.

Where to eat and drink

Cornerhouse Tea Room, off Caistor's Market Place, open daily except Monday; fish and chip shops near by. The White Hart in Caistor serves the best beer; the Salutation Inn at Nettleton serves food lunchtime and evening.

What to look for

One of Caistor's more unusual constructions is a shed built into the grassy bank at the foot of Plough Hill (down and along from the Market Place). It dates from 1869 and once housed the town's horse-drawn fire engine. Apparently the call-out fee was £3, and the tender was summoned by the tolling of the church bells.

While you're there

The walk follows some of the 147-mile (236-km) Viking Way that runs north- south along the length of the Wolds. It crosses a region occupied by the Vikings from the late 9th century. Beyond the Wolds it loops west, then heads south to finish across the Rutland border.