UNDER ARTHUR'S SEAT.

The Athens of the North has acquired a major new building which is intended to extend the city's major industry, education, while reflecting on ancient Scottish myth, landscape and tradition.

Edinburgh's historic romance derives from an extraordinary site and a townscape, from 'the most predictable to the most improbable and spectacular, and often both at once'. [1] Surrounded on all sides except the north by rugged hills, the place offers the juxtaposition of magnificent intractable nature and the man-made.

The popular image of Edinburgh, depicted by seventeenth- and eighteenth-century engravers, is the Royal Mile -- the medieval backbone of the Old Town that descends from west to east, from the castle at its head to the Palace of Holyrood House at its foot. Until now most visitors to the city have been principally drawn to the upper section, to the Castle, its environs and to the High Street. But at the other end, beyond the Canongate, the palace was isolated by slums and urban dereliction.

The Holyrood Project was conceived in the late '80s as an urban renewal scheme, funded by various means and designed to regenerate 10 acres of derelict land in Canongate -- and thereby correct the imbalance of the Royal Mile. Divided into three main sites on either side of Holyrood Road (which runs parallel to the Royal Mile), part of the scheme has provided new housing by architects including van Heyningen & Haward and Richard Murphy, and intelligent amenities such as the Poetry Library by Malcolm Fraser. But the scheme's lynchpin is a new public attraction -- the Dynamic Earth exhibition, housed in the festive William Younger Centre by Michael Hopkins & Partners, and built on an old brewery site to the south of Holyrood Road.

Across the road, next to the palace, is the site of Enric Miralles' Scottish Parliament building. At present a hole in the ground, it will constitute another popular magnet and, while not part of the Holyrood Project, it probably owes its presence in this part of the city to the project's civilizing effects.

The geological theme, informing the centre's exhibition and the building's design, celebrates the memory of James Hutton, an eighteenth-century pioneer of modern geology who lived and worked on the same spot. There are three distinct parts to the building, the most visible being an articulated tented superstructure of taut fabric (PTFE) and cables and bristling masts. Beneath are a two-storeyed building containing the exhibition, offices and workshops, and a monumental stone theatre with tiered seating in the ancient tradition.

The tented canopy, running east-west with the axis of the Royal Mile, is plainly a descendant of the amenity building at the Inland Revenue centre at Nottingham (AR May 1995), and the Mound Stand at Lord's Cricket Ground, London (AR September 1987). Counterpoised to the dark mass of landscape, to the city's weightiness and gravity, the structure has an exotic insectival appearance. As a demonstration of tension between artifice and nature (a Hopkins' preoccupation), it seems complete.

It shelters a luminous billowing pavilion which, enclosed by sheer glass walls, provides entrance to the exhibition, a civilized meeting place and an elegant cafe. It is an exhilarating space. Luminance is intensified by skylights, slivers of glass fixed to ladder trusses lifted above and separating the fabric panels of the great roof. Bursting through the centre of the floor is the hemispherical dome of the theatre below. Latitude and longitude are marked asymmetrically across its surface to give the appearance of a tilted globe, and this asymmetry working with the angled columns gives its eruption greater force.

If the canopy appears to float, the plinth on which it rests suggests an opposing weightiness. The exhibition space is a black box with offices and workshops on either side. Externally it is partly contained by an old stone wall, a nineteenth-century Tudor Gothic remnant of the old brewery, which has been restored and extended by loadbearing sandstone additions.

The third component of the centre, the monumental amphitheatre, contributes to Edinburgh's tradition of civic design. As well as proving a grand entrance and turning point for tourist buses, it will be used for outdoor performances during the annual Edinburgh Festival. Other references manifest themselves for from this quiet evocation of ancient Greece, you can sit on blocks of hewn sandstone and look across at the other evocations of Classical antiquity on Calton Hill built in Edinburgh's heroic period.