*This article is based on the latest research and historical documents (such as Parentalia) as of January 2026.

1. Proposal from the Ashes: Ren's "Baroque Dream" and its Numerical Basis

1666: The disappearance of the city and the "tabula rasa"

First, we need to accurately understand the situation at the time. Until the mid-17th century, London was a dark, unsanitary medieval city, with wooden houses packed tightly together within Roman walls and "jetties" with upper floors jutting out into the street and obscuring the sky. The urban environment was reaching its limits, with a major plague outbreak in 1665 killing approximately 70,000 people.

Then, in the early hours of September 2, 1666, a fire broke out at a bakery on Pudding Lane, fanned by strong winds and razed approximately 801 tp3t in the city. However, for intellectuals of the time, particularly Christopher Wren, a member of the Royal Society, this tragedy was also a "golden opportunity."

On September 11, just a few days after the fire had been extinguished, Len submitted a master plan to the King. It was an extremely mathematical and rational one, completely ignoring the existing property boundaries and maze-like alleyways, and drawing new lines as if the land were a vacant lot (tabula rasa).

Three core features of the Ren Project

Wren's proposal went beyond simply widening the roads. Drawing on the Baroque urban planning of Rome, which he had studied in books and had visited Paris the previous year, he sought to bring three principles to London:

• ●Hierarchical road network:
  All roads have been strictly standardized into three levels based on traffic volume: 90 feet (major arteries), 60 feet (core roads), and 30 feet (residential roads).
• ●Focal Points:
  The Royal Exchange was placed at the center, creating a star-shaped plaza with roads radiating out from it, and the layout was calculated so that churches and public buildings were always visible at the eye stop (the line of sight).
• ●Open waterfront (Quays):
  The plan was to canalise the River Fleet and build extensive quays along the Thames in an attempt to dramatically improve logistics efficiency and the landscape.

[Comparative Analysis] Revolutionary Road Width

This visual comparison shows how insanely huge Ren's proposed 90 feet (approximately 27.4 meters) figure was at the time, and how closely it resembles modern cities.

As this graph makes clear, Wren's plan was not simply a restoration project, but a revolution that would fundamentally change the scale of the city. The 90-foot road not only served as a firebreak in the event of a fire, but also represented an infrastructure investment in anticipation of future increases in traffic volume.

2. Why the plan was deemed "unfeasible": Rights and time barriers

The despair of "impossible to measure"

Why was such a rational, forward-looking plan rejected? Commonly cited reasons include a lack of funding and a lack of leadership on the part of the King, but modern research (such as that by T.F. Reddaway) has revealed that the true cause was a more structural issue: complex property rights.

Before the Great Fire, London had extremely complex land boundaries due to centuries of additions and alterations. Furthermore, there were multiple layers of rights for each parcel of land, including "freeholders" and "leaseholders," as well as sub-leases.

The Fire Court's Struggle

In the end, Charles II abandoned Wren's master plan and decided to rebuild based on the existing street network. However, it is important to note that he did not allow for "disorderly rebuilding."

In order to expedite the reconstruction, the government established a special court called the Fire Court. This was a groundbreaking system that bypassed normal court procedures and adjudicated disputes between landlords and tenants, such as who should bear the cost of reconstruction and how rent should be reduced, through summary trials. This legal mechanism was the hidden driving force behind London's rapid recovery.

3. The foundation of modern building regulations left behind by compromise

Wren's "Road Plan" has disappeared, but his "Philosophy of Disaster Prevention" has survived in another form."Rebuilding Act 1667"is.

This law adopted an approach that changed the quality of buildings instead of changing the shape of the city. Specifically, the following strict regulations were imposed:

In this way, London has transformed into a rare hybrid city, with modern, fireproof buildings built on a medieval floor plan. This was a practical solution that abandoned hard reforms (zoning) and opted for soft improvements (legal regulations).

4. To the Northern Lands: Wren Genes Seen in Sapporo and Lake Toya

Sapporo: Ren's dream of becoming a "firebreak city"

Moving forward to 19th century Japan, the city of Sapporo, built by the Hokkaido Development Commission, embodies in a surprisingly pure form the ideals that Wren was unable to realize in London.

Odori Park is particularly symbolic. This huge green space, approximately 105 meters wide and stretching 1.5 km from east to west, was originally planned as a "firebreak" dividing the city into north and south. It can be said to be an example of Ren's idea of "blocking the spread of fire with wide roads" being implemented on an even larger scale and in a more planned manner.

Toyako Town: Reverse Urban Planning in an Era of Population Decline

Now, in contrast to the present day, regional cities like Toyako Town in Hokkaido are facing the exact opposite challenges of London: a declining population and an increase in vacant land. However, here too, there are lessons to be learned from Wren's unfinished plan.

Toyako Town is a tourist destination that coexists with the active volcano Mount Usu. With the aging rate exceeding 44.0% (as of 2024), securing routes that allow the elderly to evacuate quickly in the event of a disaster is vital. If the Ren-style "90-foot road" concept were applied here, it would not be new development, but rather "ensuring ample evacuation routes by utilizing vacant land that has become a sponge."

Rather than leaving vacant lots resulting from population decline in an unregulated manner, they will be systematically connected as "green spaces" and "plazas." These will serve as places of relaxation for tourists in normal times, and as buffer zones to prevent the spread of fires and aid evacuation in emergencies. This is urban planning based on a reversed idea: "By reducing the number of buildings, we can raise the scale of the city."

5. Future Outlook: Digital Twins Open Up the Future of Adjustment

Technology can solve the cost of consensus building

The "rights adjustment" hurdle that Ren faced may be overcome by modern technology: the "Digital Twin."

By integrating not only the physical shape of a city, but also complex rights relationships, underground utilities, and disaster simulations in virtual space, it will be possible to instantly visualize "what would be the benefits and losses to each individual if this area were rezoned?" This will dramatically shorten the consensus-building process, which previously took years, and will enable "pre-reconstruction" with the consent of residents.

---