Scotland’s two biggest cities are both blessed with the sort of architecture that makes residents and visitors alike swoon. And the fact that the urban aesthetic of Edinburgh and Glasgow is so different is, to my mind, a real advantage. How lucky Scotland is to boast the glorious Old and New Towns, Glasgow’s 19th century grandeur and a world-renowned genius in Charles Rennie Mackintosh. How lucky, too, that they escaped the 20th century bombs that destroyed so much of Europe, and still provide the bedrock of our 21st century urban lives.

With this in mind, some of the architectural developments currently proposed in the two cities are, quite frankly, baffling. The economic and social implications of architecture were highlighted just a few days ago with the publication of Edinburgh World Heritage’s (EWH) latest report, which reckoned the capital’s architecture is worth £1.4bn to the economy. It added that 96 per cent of people in the city felt its built heritage was beneficial and, remarkably, 67 per cent of residents were willing to pay for it to be looked after. So far, so positive.

But EWH’s director, Adam Wilkinson, also issued a stark warning: all this economic benefit and goodwill could be wiped out if ugly new developments distort the way people view the city. He warned of “killing the goose that lays the golden egg”.

Mr Wilkinson was right, of course, to highlight such concerns at a time when Edinburgh’s councillors are allowing developers to build a giant “turd” (or a hotel shaped like a ribbon as some prefer to call it) where the St James Centre currently stands, as part of a new £850m scheme. Residents and heritage campaigners are appalled at the plan.

And that’s not the only urban building scheme in the capital causing a stooshie. The nearby Caltongate development – a sterile and unimaginative brute of a scheme if ever I saw one - has been accused by Irvine Welsh and a collective of fellow authors of “tearing apart the fabric of this great City”. The Neo-classical Royal High School, meanwhile, only narrowly escaped having two monumentally ugly wings attached in the name of providing a few more five-star hotel rooms. When I first saw the proposed plans for the iconic former school, I honestly thought it was a spoof.

Glaswegians were also up in arms last week - even managing questions at Westminster - over a development proposed for one of their city’s architectural gems, Park Quadrant. For many, including me, it seems utterly bizarre that the authorities are even considering allowing developers to build a scheme of dull luxury flats – what else? – there, especially since the proposal requires messing around with one of the city’s most admired A-listed terraces and building on much-loved urban green space.

Now don’t get me wrong, I’m not with Prince Charles on architecture matters. I don’t believe that every architectural style after 1850 is an abomination. (In fact, I think his experimental new town in Dorset, Poundbury, is one of the most hideously bizarre architectural schemes in modern Britain.) But I do think that local authorities must take our built heritage seriously, and think of long-term value as well as short-term financial gain.

Indeed, both Glasgow and Edinburgh should surely be learning from their own recent mistakes. The carbuncle St James Centre being knocked down to make way for the “turd” was only built in 1973, which seems ironic when you think that the nearby Old Town survived the Reformation.

Glasgow, meanwhile, famously knocked down considerable amounts of its built heritage to make way for a motorway in the 1960s. More recently, despite some positive ad-hoc buildings such as the Riverside Museum, it has missed opportunity after opportunity to redevelop the river Clyde into a genuinely interesting place to live, work and play.

And they should both learn from London, which has eaten itself alive in recent years with a succession of ill-advised and architecturally uninspiring towers built with no other purpose, it would seem, than to provide tax havens for the world’s billionaires. These places are a slap in the face to the hundreds of thousands of ordinary Londoners who have seen their own communities priced way beyond the means of teachers, nurses and council workers. Another side-effect of all this is that London, once one of the great architectural cities of the world, now looks just the same from many angles as Dubai, Shanghai and Mumbai. Is that what it really wants?

Some European cities, of course, have been more clever with their architectural heritage. I’m thinking of Berlin and Prague, Toledo, Amsterdam and Vienna. In these last two cities in particular, I reckon Glasgow and Edinburgh could find differing approaches to inspire them; I think of Amsterdam embracing the genuinely quirky and innovative to fit its modern, dynamic, drive, and Vienna preserving its past with immaculate, elegant pride. I can’t see the latter building a “turd” inside the Ringstrasse, can you?