Romanesque refuge: A new visitors' centre in an ancient French Romanesque abbey is conceived as a series of precisely crafted interventions.

The Romanesque ruins of the Abbaye de Montmajour dominate the surrounding Provencal landscape from the top of a hill about 5km north of Aries. When established in the tenth century by the Benedictines (it is thought as a sanctuary from the Romans), the abbey was an island refuge surrounded by Rhone marsh lands. Its prosperity began during the succeeding century, after the counts of Provence chose Montmajour as their burial place, and the abbey became one of the most important in the region.

The ruins, which now belong to the Caisse Nationale des Monuments Historiques, testify to the abbey's slow decline from the late Middle Ages onwards through fire and vicissitudes (the French Revolution was one); but, still eloquent of past wealth and grandeur, they are magnificent. Apart from remains of the great chateau of St Maur, the church is one of the largest Romanesque structures in Provence, its twelfth century crypt built into the hillside; and the cloisters, in the shadow of the great fortified watchtower, have double pillars wonderfully ornamented with a menagerie of beasts. Visitors energetic enough to climb to the top of the 25m high tower (all 124 steps) are rewarded with wide and extraordinary prospects, north to the limestone massifs of Les Alpilles and south to the sea.

The abbey is a popular destination and a plan to create a new visitors' centre in the vaulted cellars of the chateau was made the subject of a competition. It was won by Rudy Ricciotti whose imagination -- austere, dramatic, and at times, ironic and surreal -- we have seen exercised on design of structures as varied as a slender footbridge across the Han River, from Seoul to Sunyudo Island, an equally tautly designed sailing school at Bandol (AR July 1998), and the great anthracite monolith of the Vitrolles Stadium (AR February 1996), built in what was once a municipal rubbish tip. At Montmajour his approach is one that can be traced directly back, through postwar Italians such as Carlo Scarpa, who possessed an eloquent understanding of how to work with old buildings without compromising either building or architect, to nineteenth-century England and SPAB, to Ruskin and Morris.

Ricciotti's design revolves around the idea of making the new impinge as lightly as possible on the old, of creating something akin to a theatrical set; and to this end (rather in the SPAB manner) he enlisted two artists, Elizabeth Cresseveur and Josep van Lieshout and architect, Francois Deslaugiers.

In general, work included cleaning the stone and clearing and restoring openings. Old apertures have been filled with clear glass with no visible fixtures. The visitors' centre, inserted into two vast rectangular vaulted chambers with sloping floors, included creation of an entrance hall within the largest volume. It is lined down one side by van Lieshout's 15m long reception desk -- a gleaming monolith of green polyester glass resin. On the other side, the wall is lined by sliding glass panels in front of display cases, suspended from a metal rod and disappearing into hidden bases. The panels also mark the limit of a floating concrete floor, black and polished like a piece of quartz which stops short of the original shell. Like the long desk, the black river, which was poured in situ, follows the slope of the original floor and is elegantly illuminated along its edges by concealed fittings.

With Deslaugiers, Ricciotti's team worked on design of an elevated glass and metal walkway which leads up from the second chamber and is threaded through a double layer of the massive walls to the start of a circuit through the abbey grounds. Supported on single inclined columns resting on beaten earth below, the walkway is detached from walls on either side; and since the floor is transparent you have the impression of being suspended on nothing -- on light (for the structure is illuminated from beneath) and air -- floating between the weight and density of stone. (Ricciotti likens the experience to stepping across a vision of the underworld.) As the walkway passes between great arches in the wall, and outside to ground level, it turns into a glass balustraded bridge.

The ephemeral versus the substantial is a recurring theme. Fibre-optic bundles fed into a water channel carved into the wall of the entrance hall diffuse unearthly blue light; and van Lieshout's lavatories, contained in coloured pods in a separate and miniature vaulted building, emit ghostly coloured luminance.

(*.) Society for the Protection of Ancient Buildings, founded in 1877 by Philip Webb, William Morris et al.