A decidedly starry-eyed transportation pitch from British Prime Minister Boris Johnson calling for a massive underground traffic roundabout beneath the Isle of Man has been met with more than a few raised eyebrows and plenty of blistering online commentary.

Dubbed Douglas Junction after the capital of the Isle of Man, the proposed subterranean rotary would link-up a network of undersea tunnels connecting England and Scotland with Northern Ireland. As described by New Civil Engineer, a triad of tunnels—one originating in Stranraer, the second largest town in Scotland’s Dumfries and Galloway council area, another originating near Liverpool in North West England, and a third originating in the town of Heysham, Lancaster, about 90 minutes north of Liverpool—would converge at Douglas Junction where a fourth tunnel would also extend to Larne, a town in Country Antrim, Northern Ireland, just north of Belfast.

Per the New Civil Engineer, an earlier proposal dubbed “Boris Burrow” that envisioned a single, 25-mile-long link between Scotland and Northern Ireland—also via Stranraer and Larne—was scrapped by Downing Street officials due to “poor connecting transport links” in favor of a quad-tunnel affair that includes two England-originating tunnels and the underground traffic circle at Isle of Man. The roundabout would also circumvent Beaufort’s Dyke, a natural trench between Northern Ireland and Scotland that served as the United Kingdom’s largest post-World War II munitions dumpsite. The presence of the Dyke is a major obstacle faced by the single-tunnel proposal.

Located in the middle of the Irish Sea roughly equidistant from Ireland, England, Scotland, and Wales, the island is not a part of the U.K. and is classified as a self-governing British Crown dependency alongside the Bailiwick of Jersey and Guernsey, both of which are situated in the English Channel.

“The idea was that these three tunnels would meet in a giant roundabout underneath the Isle of Man and the tunnel to Ireland would start there,” a source at Downing Street is reported as telling The Sunday Times. “Everyone knows Boris wants to do this so people were asked to look at how.”

A feasibility study for the Douglas Junction proposal is expected to be approved and commence in the coming weeks although many are already doubt the ultimate viability of the ambitious Johnson-championed plan, which aims to bolster transport links between Northern Ireland and the rest of the U.K. in the wake of Brexit.

Currently, car travel between Northern Ireland and the rest of the U.K. requires a lengthy journey by ferry.

“A link between the countries would be a symbolic act of unity, especially when the little island has adopted an us-against-the-world mentality,” noted Jalopnik’s Elizabeth Blackstock of the scheme. “But it is certainly one hell of a way to achieve that goal. “

As first reported by The Times and relayed by British tabloids, the underground roundabout idea is even being dismissed by Johnson’s own aides, one of whom described the scheme as “batshit.” Another source said that Johnson is so gung-ho about Douglas Junction that it “cannot die,” adding: “Just as Hitler moved around imaginary armies in the dying days of the Third Reich, so the No 10 policy unit is condemned to keep looking at this idea, which exists primarily in the mind of the PM.”

In addition to sources close to Johnson who spoke to The Times, The London Economic rounded up a slew of online reactions, both exasperated and mocking, to the “round the bend” roundabout scheme. As one Twitter user wrote: “Roundabout under the Isle of Man?! Johnson always thinking small. I would go for tunnels through the earth’s core with 3 dimensional interchange in the centre to make CANZUK a reality. Jules Verne showed us it can be done.”

Others have criticized Johnson for dreaming up underground traffic circles in the middle of the Irish Sea instead of focusing on the COVID-19 crisis.

Alan Dunlop, the Glasgow-based architect, educator, and historian who first proposed a $21 billion “Celtic Crossing” bridge between Northern Ireland and Scotland in 2018, has also jumped into the fray.

“The reporting on the prime minister proposing a roundabout under the Isle of Man does not sound credible,” Dunlop told Dezeen. “If it is true, then I cannot think why Boris Johnson would say that at a time when there is so much criticism being levelled at the so-called Boris’ Burrow in much of the media. It only serves to undermine that which I know to be structurally, technically and physically achievable: a tunnel or bridge that connects Scotland with Northern Ireland.”