It has been said that without the New Town, Edinburgh would be little more than a glorified Stirling, and yet the capital's Georgian-era planning marvel is only a fraction of the size it could have been.
The UNESCO heritage site which is Edinburgh's New Town was built in phases between 1767 and 1850 with the aim of solving the overcrowding crisis of the Old Town and encourage the city's wealthiest residents to stay put.
The first phase saw the building of much of what is now Edinburgh's city centre between Princes Street and Queen Street, while subsequent developments expanded the New Town to the north, east and west.
READ MORE: Edinburgh's New Town was built differently to its Old Town because of the Union flag
But while thousands of magnificent terraced townhouses would be constructed during the period of Edinburgh's grand reinvention, a series of plans were dreamt up for an eastern New Town that would never see the light of day.
In 1819, the renowned architect William Playfair put forth a highly-detailed proposal imagining an elegant new quarter that would stretch north of Calton Hill as far as modern-day Brunswick Road between Leith Walk and Easter Road.
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Studying Playfair's plans, it's plain to see that streets which are today dominated by Victorian tenements would have looked vastly different both in terms of layout and architecture. Playfair imagined wide boulevards, great monuments and lush private gardens on an even grander scale than had been attempted before.
Only a small section of Playfair's 1819 plan, dubbed Edinburgh's Third New Town, would ever come to fruition, and what was eventually built would be heavily watered down.
So what caused the collapse of Playfair's proposals, and why did we end up with only part of it going ahead?
Speaking in 2020, Dr Kirsten Carter McKee, author of Calton Hill: And the plans for Edinburgh’s Third New Town, explained that the city's changing social makeup was one of the main reasons behind the lion's share of Playfair's proposals being scrapped.
"The plan," Dr Carter McKee told The Scotsman, "was to create this really impressive boulevard at Leith Walk peppered with grand buildings and monuments to come into Edinburgh in order to show the city's importance.
"This is all being proposed at the same time Regent's Street in London is being built. It's the same type of idea of residences, commercial premises and public monuments.
"Looking at when the projects abruptly stops, it's roughly around the time the railways come in. Suddenly there's a different need for the type of housing that is to be built and a new conversation on how Edinburgh should develop.
"Purely because it took so long to develop the plan, the world changed and it was never finished." Now, more than two centuries on from the publication of Playfair's plans, we can only dream of what might have been.
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