Media playback is unsupported on your device Media caption A look at some of the buildings on the shortlist

The Shard, the tallest building in western Europe, is among the designs up for a major architecture prize.

The London skyscraper is joined by Zaha Hadid's London Aquatics Centre, showcased during the 2012 Olympics on the Riba Stirling Prize shortlist.

The two designs are among six architecture projects vying for the prestigious award this year.

The prize is the Royal Institute of British Architects' (Riba's) highest accolade.

The revamped Everyman Theatre in Liverpool, the Library of Birmingham, the London School of Economics and Manchester School of Art are also in the running.

The prize is awarded to Riba-chartered architects and international fellows of the institute for their work on a building in the UK or elsewhere in the EU.

The six shortlisted buildings vary in size and purpose, but all will be judged by the same criteria - their design excellence and their significance to the evolution of architecture and the built environment.

They are:

Everyman Theatre, Liverpool by Haworth Tompkins

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The new theatre has been 10 years in the planning and has taken over two years to build. Designers Haworth Tompkins are also responsible for many award-winning theatre spaces including London's Royal Court, Young Vic, The Shed and Bush theatres.

The old buildings were deconstructed in 2011, with 25,000 of the original chapel bricks saved for use in the new theatre. The front of the building features 105 portraits of people from across Merseyside, whose images have been etched into metal shutters to create a piece of public art.

It was rebuilt at a cost of £27m, including £17m from the National Lottery. The theatre on Hope Street, which opened in 1964, is renowned for showcasing new local writers and actors. Haworth Tompkins has previously been shortlisted for the Young Vic theatre in London in 2007.

Library of Birmingham by Mecanoo

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Three stacked boxes adorned with a filigree screen are the signature of this landmark. It includes formal and informal spaces for reading, relaxing, playing and participating in the library's programme of events.

The design team was led by Mecanoo, a Netherlands-based architectural practice. Francine Houben, Mecanoo's founding partner, has described her design for the Library of Birmingham as the "people's palace" and said her design was "inspired by the energy of this great city. I hope that the adventure of going through the building will draw many more people towards the joy of learning and reading."

This is the company's first time on the Stirling shortlist.

London Aquatics Centre by Zaha Hadid Architects

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This building in Stratford, east London, was a fitting location for the 2012 Olympic Games. Inspired by the fluid geometry of water in motion, the idea was to create a space and a surrounding environment in sympathy with the river landscape of the Olympic Park.

The undulating roof sweeps up from the ground like a wave to fold over the building and define two separate pools. It also houses a diving pool. The complex is now open to the public, while also being a training base for the likes of British Olympic bronze medallist Tom Daley.

Hadid is a two-time winner of the Riba Stirling Prize, having picked up the award in 2010 for Rome's Maxxi museum and, in 2011, for Evelyn Grace Academy in London.

Analysis by Will Gompertz, Arts Editor

There is no obvious collective aesthetic style in the shortlist for the 2014 Riba Stirling Prize, nor is there a unity of purpose. The designs weren't built at the same time. Zaha Hadid's London Aquatic Centre was a highlight of the 2012 Olympics, an event which took place in the same summer Renzo Piano showed me around his completed but then un-let "Shard".

I suppose one could point out that they are all - to an extent - public buildings. Each is making some sort of public statement of intent, from Library of Birmingham's role as the physical manifestation of the council's ambition to make the city an international hub for the new knowledge economy, to Liverpool Everyman Theatre's mug-shot-covered facade announcing its art-for-all philosophy.

Like the culture in which these buildings exist, the emphasis is on the individual and the ego. Clients want "starchitects", or at the very least designs that boldly stand-out rather than subtly fit in.

Read Will's in-depth analysis of the short-list

London Bridge Tower (The Shard) by Renzo Piano Building Workshop

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Accommodation totalling 1.2 million sq ft (111,500 sq m) has been built on a small parcel of land directly next to one of London's major transport hubs. It is used to house a health clinic, offices, restaurants, a hotel, residential apartments and a public viewing gallery, and has become an integral part of the London landscape.

Taking inspiration from the spires of London churches and the masts of tall ships depicted by the 18th-Century Venetian painter Canaletto, Renzo Piano designed the "Shard" as a spire-like sculpture emerging from the Thames.

Eight sloping glass facades, the shards, define the shape and visual quality of the tower, fragmenting the scale of the building and reflecting the light in unpredictable ways. This is the company's first nomination for the prize.

London School of Economics (LSE) - Saw Swee Hock Student Centre by O'Donnell + Tuomey Architects

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The first new building LSE has commissioned in more than 40 years, Saw's dramatic sculptural form and unusual perforated brick facade was designed by Irish architect O'Donnell + Tuomey. The building opened its doors in January this year.

Built on a small, uncompromising site in central London, it is formed as a continuous spiral rising upwards, the outer brick walls sloping and twisting, gouged with cuts and cracks to give light and form. It is home to the university's students' union and includes a faith centre, gym, bar and several cafes.

O'Donnell + Tuomey was shortlisted for the Stirling Prize in 2012 for the Lyric Theatre in Belfast.

Manchester School of Art by Feilden Clegg Bradley Studios

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This project involved a major refurbishment of a 1960s tower plus a series of steel-braced oak staircases and bridges to connect the different levels of this extension to the main 19th Century building.

The new building provides additional studio, workshop and exhibition spaces for the school's 3,500 students and features a seven-storey glazed facade, which creates an exhibition and events space that can be seen from the street outside.

Referencing the aesthetic of traditional local warehouses, the architects applied industrial materials including concrete, steel and glass throughout the interior. Feilden Clegg Bradley Studios won the Stirling Prize in 2008 for its Accordia housing in Cambridge.

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