Drum role.

On the south-western extremity of the city of Madrid, the massive stone arches of the old Toledo Bridge span the Manzanares River. From here, the long Calle de Toledo leads upwards to the Plaza Maior skirting the Puerta de Toledo on the way. This overbearing monument built in the early nineteenth century (to commemorate the return from banishment of the harsh monarch, Fernando VII) stands in the centre of an eponymous roundabout. Formerly isolated, physically and symbolically, the Gate's historic role as a triumphal arched breach in the city wall was restored by Juan Navarro Baldeweg's plan designed during the 1980s to make sense of the urbanistically incoherent area (AR June 1987). As part of the plan, Navarro Baldeweg anchored the Gate to its urban context by placing two buildings to the north of it on either side of an axis continuing the Calle de Toledo. The buildings, a social centre and a recently completed library, were conceived as a pair of symbolic gatehouses which are set asymmetrically on mirrored plinths of grey granite, the former an existing outcrop, the latter man-made. From the top of each one, two curving ramps step down symmetrically to ground level, their geometry responding to the curve of the roundabout. Seen from the south, the composition made by the Gate with its distant frame appears complete.

Navarro Baldeweg's feeling for the dynamics of space and for subtle balance, in contrast to rigid symmetry, is that of an artist (he trained first as a painter and sculptor); as is his emphasis on architecture as a medium for expressing natural phenomena, such as gravity and light. The Puerta de Toledo library is one of a series of buildings employing archetypal form -- the domed drum floating above an earthbound base -- to convey both timelessness and gravity, but its particular configuration in the first instance came out of Navarro Baldeweg's perception of the context and of its role in it. In this case, the elemental form of the drum, clad in white stone, retreats from dominating the street and Gate. It is set back on its plinth to form an airy terrace that, like a mirador, overlooks the street. Entrances on either side of the drum give direct access to the reference library. The clearly drawn silhouette stands but as a civic building; and in its spare proportions and form, it is most obviously reminiscent of Asplund's Stockholm library; though there are echoes of Stirling's Staatsgalerie in Stuttgart.

The building contains four floors: two contained within the plinth, and two in the elevated drum; but it is the cylindrical form of the latter that dominates the plan; space and the circulation routes that serve it are spun around as if by centrifugal force. In the basement is a children's library with an independent side entrance, and connection to the main entrance hall. There is room for 800 readers, and reading and activity areas; as well as the general book stack and plant room. Above at street level, is the main entrance hall lit by a glass skylight at the junction of drum and plinth. Within the drum's circle is the lending library, with 40 000 books set out on radiating metal shelves, easy to use and overlook. Outside the circle, the space is occupied by an auditorium for 70 people, offices and lavatories

The reference library is on two floors underneath the dome, held within the cylindrical space and split to allow light from the dome to penetrate the lower level. Metal shelving following the curve steps up to the reading room above.

Navarro Baldeweg's celestial manipulation of light by means of a central oculus within a dome occurs in several of his works (for instance, the Salamanca and Cadiz conference centres, AR May 1986). Here, his handling of light takes on another dimension. Interposed between the domed ceiling with its oculus and the readers, Navarro Baldeweg has suspended a glimmering metal baldacchino which sheds light and shadow over the white interior of the drum to diffuse gently onto the desks below.