Finnish Acropolis.

A remote village in rural Ostrobothnia celebrates its renowned folk music festival and its unusual topography by turning its hill into an acropolis.

Ostrobothnia, the land to the east of the Gulf of Bothnia, is one of the world's most enervating places scenically. Absolutely flat, its forests seem from the militarily straight roads to stretch for ever, relieved occasionally by lakes and meadows. So a hill, no matter how little, has great importance.

The new Centre of Folk Art at Kaustinen, a little village in central Ostrobothnia, celebrates the small mound-like eminence in the centre of the municipality by burrowing into it and turning it into an acropolis. The village is unusual in the area, for many small Finnish settlements were vilely redeveloped in the name of progress when Finland became prosperous in the '70s and '80s. But Kaustinen's centre is not very badly mutilated, and its structure, with wooden houses surrounding the church, is still clear. It has long been a centre for a folk music festival, and the hill is topped by a dance and rock pavilion (the Finns are very fond of dancing) and a sports centre with a ski jump. The Folk Art Centre climbs up the hill in a series of terraces connected by grand public stairs. The main approach is from the town to the west. You are met by a propylaeum which consists of the timber-covered arc of an open-air theatre and its wooden scena which inflects you towards the ascending terraces by which you approach the entrance.

The terraces are contained by rectangular wings which house, to the south, the cafeteria and shop, and to the north, the galleries of traditional folk art, principally of musical instruments. Severely rigorous geometry is somewhat softened by the fir board cladding, which is treated and made ruddy and fragrant with a mixture of tar, linseed oil and turpentine. The wings emerge from the hill and funnel visitors up the terraces to the entrance foyer, the spatial hub of the place.

Steps (quite steep ones) continue up the hill over the foyer, so that it is partly underground. It opens the workings of the organization to the public on several levels, up and down. Two galleries fly across the space connecting the wings. Immediately ahead is a bridge-ramp which gently slopes down to the doors of the auditorium over the temporary exhibition space at a lower level.

Even though it is partly dug into the hill, the foyer is a light and cheerful place, with illumination coming from above as well as the sides. Light is reflected from the pale grey polished concrete floors, and from the latch boards which line most of the vertical surfaces; they are made slightly warmer in colour than usual by being lightly washed with tar, a treatment that appropriately gives the whole space a smoky aroma, reminiscent of traditional timber peasants' huts.

If the foyer is the most articulated space in the complex, the auditorium is the most powerful and mysterious. A rectangular artificial cavern, a hall for a Finnish mountain king, has been carved out of the hill with raw rock walls sloping down to an ample stage. A suspended grid of heavy timbers partly conceals the gunite roof, and accommodates services. What could have been a grim space is relieved by the spruce-clad wails of the lower part, and light spruce-framed furniture, both of which also modify the reverberant qualities of the space.

Putting the hall inside the hill has the advantage of hiding its large volume, and the arrangement of the external forms (and their cladding) ensures that there is a kinship in scale and material between the new complex and the largely timber buildings of the village. But it is the handling of the route and external spaces that gives the complex real distinction. The hill has become an acropolis (even if it is somewhat oddly crowned by the older rock music hall), and progression up and down (when the village dominated by the old church fills the view) has acquired some of the dignity and drama to be found in ancient Mediterranean celebratory routes.