What lies beneath may come as a pleasant surprise

New Zealand took all the location credits for the movie version of Lord of the Rings. Yet the ideal place to find a home fit for a Hobbit is the Loire Valley. The region might look like a serene expanse of river, countryside and châteaux, but delve more deeply and you discover it is riddled with holes. Many are natural (the result of millions of years of rainwater eating away at the porous limestone); others are man-made. And one of the most intriguing facets of the area is how they have been harnessed by man.

Aim west from Montsoreau, for example, on the road above the riverbank. The map bears a cryptic "Trog.", short for Troglodytes. You soon encounter a cliff that resembles a shopping mall for the Flintstones: a sequence of caves adapted by artists and craftspeople to sell their wares. Further on, around Saumur, the spaces have been created by quarrying tufa - the fine white limestone used to build Westminster Abbey and other notable structures. The village of St-Hilaire-St-Florent has mainly been colonised by the makers of sparkling wine, but it is also the hub of French mushroom production; you can visit the Musée du Champignon any day of the week. Elsewhere in the area, potteries, distilleries and restaurants fill the voids.

For the most intriguing glimpse of life underground, though, travel 28km west of Vendôme to the village of Trôo, which occupies a crumpled hillside on the right (north) bank of the Loir. At first sight, it looks pretty but ordinary: layers of terraces dotted with cottages lead to a hilltop church. Yet there seem too few houses for the population of 350. On closer inspection you find that many of the residents have built inwards rather than outwards. The limestone ridge is riddled with caverns that are just the right size to live in.

Troglodyte residents with properties that abut the main road have adapted to their public prominence by grafting elaborate gables on to the rock face. Such façades are rare once you climb above the D917, and many of the troglodyte residences seem almost camouflaged. Walk at random along paths, and suddenly you happen upon a front door flanked by a couple of windows. These provide the only natural light to the cave, and accordingly the living areas tend to be close to the mouth of the cave.

For modern man and woman, cave life can be surprisingly comfortable. The interior becomes increasingly dark as you move deeper into the raw rock, and the sleeping quarters are towards the rear. The result: the quietest night you will ever experience. The Hobbit had the right idea.