Atacama oasis.

Drawing on vernacular forms and passive methods of environmental control, this hotel for adventurous travellers in Chile's northern Atacama Desert is a highly poetic response to light, landscape and climate.

Chile's northern Atacama Desert is one of the hottest, driest, places on earth. Scorched by day and chilled by night, the desert plateau is bounded by the rugged cordillera of the Andes to the east. The light is unusually strong, intensified by clear skies and very low humidity. Eclipsed by the harshness of topography and climate, humankind's impact on such a remote and inhospitable place seems precariously fragile.

Yet for 3000 years, native peoples have resiliently and ingeniously exploited scarce natural resources to colonize the Atacama wilderness. Indians descended from ancient Inca and Tiahuaniaco civilizations built canals and aqueducts to irrigate fields, using water drawn from underground aquifers. Scattered settlements were established around water sources and when the Spanish arrived in 1500, the native populace adapted to and absorbed colonial influences. Relying on thermal mass to regulate internal temperatures, indigenous buildings are low-slung, almost topographic presences in the landscape, enclosed by thick adobe walls.

The region's main centre is San Pedro de Atacama, laid out by the Spanish in the early sixteenth century on a grid extending from a central plaza. On the south-west outskirts of the town lies German del Sol's new Explora Hotel. Conceived as an elegant, hospitable haven, Explora offers travellers and jaded urbanites scope to explore and experience Chile's often sublime landscape. The new hotel is del Sol's second Explora venture; the first was in the Torres del Paine National Park in equally remote southern Patagonia.

Siting the hotel on the edge of the town clearly distinguishes it as an object building in the landscape. lt echoes the Pre-Columbian custom of using built structures to mark and define places, so establishing multiple relationships with nature. (The antithesis of this is the colonial street grid, in which buildings form part of an artificially imposed order.) The hotel complex appears as a series of long, low bars in the landscape, like a sprawling estancia ranged over the arid fields. It consists of a main two-storey block, with four adjoining single-storey guestroom wings. The narrow wings snake and splay off to enclose a trapezoidal patio courtyard. Responding to the form and substance of the land, fractured geometries predominate, giving the complex an elemental, geological quality and humanizing the scale. The massive, white rendered volumes are crowned by layers of wide, overhanging roofs clad in strips of timber and copper.

Dining and social spaces are placed on an elevated piano nobile level in the main block, with vistas out over the guestroom wings to the desert and distant mountains. The generous, irregular volumes of the entrance hall, bar, restaurant and lounge are languidly disposed round a more tightly planned L-shaped service core of kitchens, offices, and staff dining room. The two zones are separated by a wide internal street lit by tall clerestory windows. Drawing on traditional Atacaman forms, the organic fluidity of the plan blurs distinctions between public and private, interior and exterior realms. Verandas and terraces wrap around the piano nobile, acting as informal extensions of the principal spaces. Below, at ground floor level, lies a labyrinth of staff quarters, service areas and a small exhibition space devoted to artefacts from the region.

Guestroom wings are also slightly raised above ground level, to frame and isolate views. The long horizontal volumes are minimally articulated with a continuous strip of window, emphasizing the simple, monolithic building form. At present the hotel can accommodate 100 guests in 50 rooms, but there are plans for a second phase that will double capacity. Even so, the scale of development is relatively and necessarily modest. The gently curved roofs of each guestroom wing oversail to create a sheltered colonnade that winds around the perimeter of the patio courtyard. Carob, oak and pepper trees also provide natural shade.

Controlling the intense desert light proved one of the most testing challenges of the programme. The roof plane extends beyond the building line to shade and protect the intermediate veranda spaces. Overhanging sections of the roof are constructed from timber slats with slight gaps in between which filter and diffuse the sun's glare in a delicate, shimmering pattern of striated shadows. The roof structure consists of two sections- a curved upper part and a lower flat roof. Light and air circulate between the two layers and into the spaces below through a series of skylights. Soft half-light-penumbra - washes over the timber ceiling, dispersing evenly through the interior.

Against the predominantly white walls, colour is used sparingly, applied to elements that can be touched, such as doors, window frames and furniture. A palette of bold red, blue, green and gold - hues commonly used in vernacular buildings - invigorates the penumbra, bringing life and colour to the cool, luminous spaces.

Several outlying structures on the site were also restored to form part of the complex. Remnants of irrigation ditches were rebuilt and refilled, so in the Moorish Hispanic tradition, the sensuous presence of water animates and temperates the site. Existing adobe dwellings were refurbished for the use of local guides employed by the hotel. Angular boardwalks twist through the landscape, linking the hotel with slate-lined bathing pools. Small sauna cabins appear as startling, white cubes in the barren terrain.

Compressed between earth and sky, the hotel becomes part of the Atacama landscape. Visitors can climb on to roof terraces to commune with nature; beneath their feet, the copper-clad roof forms meld and merge with the desert. Del Sol's architecture is a poetic architecture of place that seeks to embody the very particular culture and spirit of Atacama. It is also an architecture

of ecology, of enlightened mediation between extremes in response to light, landscape and climate.