“The high-quality Swiss architecture,” says Christoph Gantenbein, “is not homes. It is the tunnels and dams and bridges withinside the Alps. That’s in which it’s miles at its maximum effective.”

Gantenbein is status withinside the gaping exhibition corridor of his personal bridge-cum-dam-cum-cliff-face, which now zigzags its manner across the returned of the Swiss National Museum in Zurich, a giant piece of civil engineering withinside the leafy surrounds of Platzspitz park. Poking its beady round eyes above the trees, it looks as if a few exceptional concrete leviathan, writhing up and down in angular waves underneath the fairytale turrets and spires of the 19th-century museum.

If concrete gymnastics are certainly considered one among Switzerland’s proudest ability – along penknives and posh chocolates – then this effective new extension, set to open in July, is surely an apt shape for the repository of the country’s cultural history. Walking thru its voluminous shell (but to acquire the exhibition fit-out), up enormous staircases among sloping-roofed halls, dotted with enigmatic constellations of porthole windows, it looks like exploring the cavernous depths of a secret Alpine lair. Ernst Stavro Blofeld is probably lurking round each certainly considered one among its acute corners.

Fourteen years and 111m Swiss Francs [CHF] (80m) withinside the making, it turned into the primary foremost task its architects won, in an open global opposition in 2002, on the soft a long time of 30 and 31 – slightly foetal in architectural terms – once they failed to actually have a finished constructing to their names. Delays as a result of ministerial price range wranglings and the vocal competition of the rightwing Swiss People’s Party (whose posters bewailed this monster taking up the park), suggest that Christ & Gantenbein have in view that come to be one of the country’s maximum sought-after practices.

They have constructed a portfolio of angular rental blocks, faceted workplace homes and a shimmering lozenge-formed tower, in addition to their personal monograph, professorships at ETH Zurich and Harvard, and a style click in Italian Vogue – their sharp fits and appropriate seems coming as chiselled as their homes. Cementing their role because the go-to architects for tasks of countrywide pride, they are now designing a brand new traveller centre for the powerhouse of posh chocolates, Lindt & Sprüngli.

So all eyes had been on Basel remaining weekend for the hole in their cutting-edge task, a brand new 100m CHF (73m) constructing for the city’s Kunstmuseum, domestic to the oldest municipal series of artwork withinside the world. The end result of an global opposition in 2009, wherein Christ & Gantenbein smack a bunch of global stars, which include Zaha Hadid, Rem Koolhaas and David Chipperfield, it’s miles every other sharply sculpted mineral shape of monolithic heft, however one which does a good buy extra than their Zurich zigzag to ingratiate itself with its surroundings.

While the expressive extension to the National Museum turned into dreamed up in what Emanuel Christ calls “a second of innocence”, and exudes a younger urge to make an iconic mark, the Kunstmuseum is a version of delicate maturity. As Christ places it: “There is now extra of an internal urgency for order, for a stricter machine and structure, in an nearly classicist sense.” They are older, wiser, and do not want to shout pretty so loud.

For a group that spans the beyond seven centuries, their constructing has a definitely undying quality. It stands at a junction, throughout the road from the prevailing Thirties museum, with a geological presence, as though it’d were hewn from the facet of an Alp in a single chunk. Three sun sunglasses of skinny gray bricks (with 3 matching sun sunglasses of mortar) deliver the facade a stratified, sedimentary quality, organized in bands that nod to the classical composition of base, piano nobile and frieze followed via way of means of its neighbours. Laid in alternating projecting guides, the bricks shape a sort of corduroy surface, the horizontal grooves recalling the facades of Romanesque church buildings in Italy, expecting the stone dressing that by no means came.

It might be a damage from every other time – besides that the frieze, in a second of cloth alchemy, carries strips of LED lighting fixtures hidden among the guides of brick, permitting textual content and pix to emanate from the wall in a manner that makes them appearance published directly to the masonry. It’s a small detail, which might be garishly clumsy in different hands, however carried out right here with a manipulate regular of Christ & Gantenbein, combining historic and current in a beguiling new manner.