The designers of the London Eye, architects Marks & Barfield, are confident that their upwardly mobile replacement for the wrecked West Pier will be open by 2011. Work has already begun on the i360 project which has already been dubbed an 'iSore' by its critics. It will consist of a 100-person fibreglass pod which will gently rise up a 144 yard tall steel cylinder, giving unmatched views of the city, sea and downs.

Marks & Barfield place their design in the tradition of other south coast examples of pioneering architecture (presumably such as the modernist De La Warr Pavilion). The seaside attraction will be topped by wind turbines which will provide some of the power needed to operate it. The West Pier Trust still hopes it will eventually rebuild the elegant pier which was the star of Ken Russell's 'Oh what a lovely war!' as well as featuring in several of the 'Carry On' films.

I do like lists. For the prevaricator, the making of them is a satisfying way of delaying the work itself. For the anorak (and we all secretly have an anorak within, don't we?) lists are all about neatness and order and collecting. Like butterflies pinned down under glass, lists fix the worryingly mutable world.

The UNESCO list of world heritage sites satisfies several of these instincts. Is the list complete? What are the selection criteria? Which have I been to? Where to next? In England, Bath; Blenheim; Stonehenge; Westminster; Durham and Canterbury all make their expected appearances. But not Oxford or the landscape gardens at Stowe or Lincoln or Wells Cathedrals or Windsor Castle? And what about the Lake District?

The most recent UK addition is the newly cleaned-up satanic mills of Cornwall and West Devon. Other 'post-industrial' tourist sites are Saltaire (worth a visit but is it a world heritage site to match the tower of London?) and Derwent Valley Mills where Richard Arwright worked and there are '680,000 bobbins on display'. That is a lot of bobbins. And should I mention Liverpool?

In Sweden there are several longwave masts just waiting to be admired. And Bauhaus architecture in Tel Aviv, too. It's evident that some countries are better than others at agenda pushing.

Reasons for smugness, and for poetry: Bruges, the Plantin-Moretus, Split, Dubrovnik, Trogir, Chartres, Mont St Michel, Amiens, Versailles, Pont du Gard, [the whole of?] Bordeaux, Paris, Cologne, the Vatican, Prague, Budapest, Vienna, Florence, Pompeii, San Gimignano, Vicenza, Sienna, the Amalfi, Naples, Verona, Tivoli, St Petersburg, Alhambra, Guadi, Ibiza, Drottningholm, Göreme, Istanbul, Troy, Pamukkale [no Ephesus?], And the Stautue of Liberty and the The Red Fort, Fatephur Sikri and the Taj Mahal. And some others I missed.

But I was reassured to find plenty more for my own heritage site 'to do' list. Khajuraho, Aachen, the Acropolis, Mount Athos, Ravenna, Rietveld Schröder House, Butrint in Albania (been wondering about it for ages), Sintra, Valetta. Mérida, Salamanca, Route of Santiago de Compostela and a reassuring heap of places in former Soviet Republics including Riga, Český Krumlov and Tallin. And with less footprint, Hadrian's Wall and the Giant's Causeway.

That's enough lists.

A quick trip to London's Number 1 Poultry today. If you can get to the impressive roof garden there are stunning views that more than make up for the irksomely courageous whimsy of the controversial architecture.

Peter Palumbo spent decades acquiring the site site piecemeal from 1958. His scheme to demolish the listed Mappin & Webb building and replace it with what Prince Charles called a 'giant glass stump' - a monumentally impressive bronze coloured steel and glass tower by Mies van der Rohe - was decisively thrown out in 1984.

Palumbo's answer to his critics was to appoint RIBA medal-winner James Stirling to design a vigorously jokey post-modernist block.

Stirling thought he had only a 50-50 chance of success. "I do regard this site as being very special, at this spider's web intersection surrounded by all those heroes like Lutyens and Hawksmoor and Dance. It's the quintessence of London."

Like a stranded submarine decked out in pink stripes, the triangular building seems desperately to be sailing its giant conning tower up the slope towards the Mansion House. The stepped frontage ripples with fiddly bits. Triangles are punched out of the facade and theatrical games are played with circles and squares. The building has a bunker-like rear that currently accommodates a Wetherspoons.

But it uses Portland stone and granite, and it contains echoes of the old buildings on site (if anyone remembers them) so it could hardly upset the purists, could it? Could it ever. Prince Charles demonstrated his familiarity with the latest technology when he said it looked like a 'broken 1930s wireless set'.

Delayed by recession, the design was posthumously completed after Stirling died at the hands of an incompetent anaesthetist. Since then it has regularly won polls for both the best and worst building in London.

Walk into the open rotunda at the centre of the development (with its irritating Dayglo coloured window casements) and take the lift to the Conran-run 'Coq d'Argent' roof garden restaurant and a whole new impression forms.

Wisteria and hawthorn flourish. Fragrant box hedging leads to stunning views of the gherkin and Wren City churches from the glass ship's bridge, either side of the conning tower. Well worth a visit, especially on a Sunday when the people paid to keep rubber-neckers away from the rooftop are less likely to be on duty.

“If you start to take Vienna - take Vienna” said Napoleon. A tall order for the art-lover with just four days in which to attempt to do justice to the major sites. The Kunsthistorisches, the Albertina, the Belvedere, the Imperial Library, the Ephesus and the Musical Instrument collections, the Hofburg, the Schönbrunn. The Cathedral, the Karlskirche or the Peterskirche? Canova, Dürer, Caravaggio or Vermeer? Baroque or Secession?

All the booty of empire gathered within the 4km ring, lined with palaces cascading with statuesque caryatids and writhing atlantes. Churches with walls coated with plaster angels forever tumbling into the inferno. A Haydn, Mozart, Beethoven or Strauss commemoration on every corner. And the cakes!

Vienna oozes history and its unconcerned citizens embody a favourite word of Queen Victoria's. They and their city are 'Gemütlichkeit' - contentedly belonging, polite and unhurried. On the plane a Viennese offered tips on getting the best from his home town. In the Graben, the city's busiest shopping street, half a dozen people stopped and waited while I pointed my camera up at a building across the street. At junctions cars halt and pedestrains are waved across. Gentlemen of a certain age wear hats. Their ladies are impeccably (and somewhat conservatively) dressed. Even the frock-coated touts for Strauss concerts are polite in their salesmanship.

We marvelled at the Prunksaal of the Imperial Library with its ravishing ceiling decorations and perfect proportions, justifying the claim that it is the finest library hall in Europe.

Mohr in Hemd (chocolate pudding) or Kokosbusserln (Coconut Kisses)? The cakes are as elegantly refined as the Viennese. We ate Sacher torte in a relaxed and splendidly old-fashioned café by the rear entrance of the Hofburg Palace. A Secession facade there so offended the emperor with its 'plainness' that he reputedly never passed it again. 

We resisted other temptations including the discrete entrance of the exotically Turkish Centralbad which was a haunt of the Archduke Ludwig Victor, a brother of the emperor Franz Josef I, who 'was famous for his love for beauty'.

We admired Canova's tomb for Maria Christina at the Augustinerkirche. It was such a success that Canova himself was buried in a copy in the Frari in Venice. In the Kunsthistorisches we ate more cake and lost hours in the galleries. Not one but three Rembrandt self-portraits. Exquisite Roman cameos and gold jewellery quite unlike anything I had ever seen. 

An incredibly myopic Jehovah's Witness seemed to be stalking us in the clock museum. All three floors are choc-a-bloc with chiming timepieces. He was a museum warden and seems to spend his days reading scripture, held at about 2" from his nose. In the museum of musical instruments (rooms of shawms, serpents and Beethoven and Chopin's pianos) another warden was nervously writing who knows what never to be published masterpiece on scraps he carried round with him.

Austrian Art Nouveau toyed with plainness but finally embraced ornament with relish. We admired Otto Wagner's Majolica House which is a riot of coloured tiles and ornamental balconies. The secession building has a glorious gilded dome of glittering laurel leaves. More pictures here.

Given John Prescott MP's unlikely reputation as a lothario, it seems right that he be remembered for giving permision for London's most thrusting new erection - Renzo Piano's 'shard of glass' at London Bridge. Piano describes it as "a vertical town for about 7,000 people" based on "London's heritage of masts and towers".

And since economic ruin is aparently just around the corner what are the chances that financially it doesn't quite rise to the occasion? If it doesn't all go quite according to plan it's apparently the Qatari governement that will get their fingers burnt.

Building a tower taller than everyone else's is not an especially female obsession. Skyscrapers are the phallocratic bullies on the block: they shout down their neighbours, and as Piano says, have a reputation for "arrogance and mysteriousness". He hopes the shard and a matching 'baby shard' nearby will be lively, open spaces, available for the public's pleasure 24 hours a day.

An article in Building Magazine describes the construction of this new 310m high, 88-storey skyscraper, with some excellent animations. The developers promise surgical operations in Guy's Hospital next door will not be disturbed by the £350m work, and that the trains will still run (almost) on time at London Bridge station. Piano's racy design includes a hotel, the inevitable offices and a viewing platform near the top. If you put the Gherkin on top of St Paul's, the shard will still be 21m taller.

Outside Europe they do it bigger. In Dubai they are putting up a tower which will have a spire that will reach 818m, with the 164th floor 194m below. There's even a dam in Tajikstan which at 300m is almost as high as the shard will be.

A pity that all the materials for Prescott's needle will travel by road, even with a major rail terminal next door. If it all goes to plan we should be enjoying the view by June 2011.

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