IRISH PROMENADE.

Refined in its detailing and elemental in its use of materials, the Irish pavilion is a cool, tranquil cave providing refuge from the blare and bustle of the Expo site.

Surrounded by the razzmatazz of the Hanover Expo site, the visitor's instincts may well be to hide, to retreat to somewhere cool, natural and elegant. Ireland's pavilion offers the fugitive a cave-like and undemanding architectural promenade. It is a building of admirable tectonic simplicity (although some of its contents threaten to distract), in essence two stone walls, a pool of water, some ramps, a sheltering roof plane, and an inner 'intelligent' wall, housing various art objects, text, and a lively video presentation.

The north wall is made from gabions, the south of polished black Kilkenny limestone. Perpendicular to the Expo boulevard, the gabion wall is 54m long by 1 10m high. It consists of metal mesh cages slotted between steel columns at 3m intervals and filled with local stone. A metal plate is embedded between the gabions for fire protection. The polished south wall is of two parallel layers screening services and a small lift. Slightly shorter and slightly lower than its gabion companion, it is canted in plan to produce a forced perspective between a hovering piano nobile and the ceremonial pool which leads beneath.

The theme of nature and new technologies is established at the entrance, where thin perspex reeds are illuminated by incandescent lights. A large glass panel slides automatically to allow passage upwards against the limestone wall (decorated by artist Tom Fitzgerald as an unfolding pictogram) and between a row of stone columns (some structural, others housing glass exhibition cabinets). The limestone wall contains a series of clefts in which the visitor can handle seaweed and feel 'Irish rain'; sounds of laughter can also be heard.

Carved out of the opposite gabion wall are four vertical recesses (part side chapels, part boutique installations) with stone, willow, hazel and rock salt stacked into columns. Another artwork, by Martina Galvin and a group of Dublin schoolchildren, filters light through the expansive, glazed west end. A 180 degree turn brings the visitor into the pavilion's main space, a generous ramped hall with a multi-screen video by Clan De Buitlear. The floor, laid in concrete payers delineated by oak strips, is held clear of the longitudinal walls with metal grilles to allow free movement of air and occasional glints from the pool below.

The promenade ends at the east-facing opal-glass facade, with a transparent band above the entryway; then exits through a conservatory outside the limestone wall. A VIP route cranks back inside to pierce the gabions and reach an administrative wing. This saddlebag of offices and restrooms and an entertainment suite hangs free of the pavilion above the ground. It is clad entirely in shiny corrugated metal -- even window openings have perforated metal outer skins. The conservatory is less impressive, a glass cage framed in pine but lacking any programmatic function (apparently a small shop or cafe proved impossible to arrange with the Expo authorities).

In keeping with the stated ambitions of Hanover, Ireland's pavilion engages with several issues of sustainability. As a temporary structure, it is not subject to some of the stringent building codes that other participants must follow.

Rainwater is gathered from the roof and fed into the pool, which is kept fresh by small level changes and the introduction of rocks and environmentally kind additives. Air is taken up from the pool, circulated throughout the building and expelled from the roof. There is a small solar collector above the administrative wing. In principle, the building is demountable and may be re-erected next year in Ireland.