Architecture in 2012: review of the year in buildings In a year that saw severe funding cuts to schools, libraries and arts buildings and the delivery of new housing rattling along at its lowest level since records began in the Twenties, there weren't too many rays of light for British architecture. And yet one, at least, shone brightly. By common consensus, the transformation of 560 acres of contaminated former industrial land in east London into the Queen Elizabeth II Olympic Park was a national triumph. Here, finally, was proof that, when we put our minds to it, we have the capability to transform our cities for the better, making places that people want to visit and, hopefully before very long, live. The 20-year project of building new neighbourhoods around this beautifully landscaped space studded with exemplary public buildings promises to be an achievement every bit as substantial as the construction of the park itself. The Olympic deadline proved an impetus for projects elsewhere in London too. John McAslan and Partners" curvaceous western concourse at King's Cross station finally addressed what had long been one of the capital's more tawdry gateways, although a major dividend of the project - the removal of the wretched and supposedly short-term concourse that was tacked onto the front of the station in the Seventies - is only now being realised. The restored view of the principal elevation of Lewis Cubitt's wonderfully severe 1852 shed and the public space by Stanton Williams that is being established in front of it promises to be one of the great architectural treats of the coming year. Also completed just prior to the Olympics - at least in its external details - was what inevitably proved the most divisive building of the year: the Shard. Designed by the Genoa-based Renzo Piano, this craggy spire formed of tilting facets of sheer glass rises more than 50m above the next tallest building in the European Union. As a gesture on the skyline, it undoubtedly impresses, but quite why the capital needs tall buildings outside the City of London and Canary Wharf remains far from clear. What is certain is that a great many more are soon to follow and many of them of considerably less inspiring design than the Shard. Rafael Viñoly's top-heavy Walkie-Talkie is already shooting out of the ground on Fenchurch Street and proving to be every bit as oafish as the computer renderings suggested. While construction activity outside the South East remained sluggish, it still managed to produce the occasional special building. Following the 2011 completion of O'Donnell and Tuomey's Stirling Prize-shortlisted Lyric Theatre in Belfast, it was particularly heartening to see Northern Ireland deliver two first-rate public projects. The Giant's Causeway visitor centre by Heneghan Peng is a building of exemplary tact, cut ingeniously into the ground so as not to encroach on the landscape in which it is set. The building's use of basalt and its complex, faceted geometry make for an architectural experience that bears a vivid relationship to the extraordinary local geology. Hackett Hall McKnight faced the opposite problem in designing its MAC arts centre in Belfast - the building's immediate environment comprises a catastrophically misjudged commercial development that their project couldn't do enough to ignore. From this unpromising start, the local practice has none the less mustered a hugely powerful if introverted building. This was the young firm's first major building and offered convincing evidence that it is one of the major British talents of its generation. Another young firm that realised what will hopefully prove a breakthrough project is Witherford Watson Mann. Costing £2.5 million, its remodelling of the ruined 800-year-old fabric of Astley Castle, outside Nuneaton, may have been a more modest undertaking than many of the year's landmark buildings, but it was the one that moved me most. After the building was consumed by fire in its last incarnation as a hotel in the Seventies, the Landmark Trust devoted decades of effort to securing its future. However, plans to see it fully restored ran aground in the face of prohibitive costs, requiring the adoption of a cheaper but considerably more inventive plan B. Witherford Watson Mann's light-touch intervention protects what remains of the fabric from further decay while establishing within this broken shell a smaller residence which is now available for short-term let. When adding to existing buildings, contemporary architects all too frequently make a drama of the contrast between new and old, but here that relationship is forged with delicacy. The architects have achieved something marvellously holistic without seeking to erase the building's troubled history. The new works read as just the latest episode in a centuries-long process of continual adjustment.