Ingenious Flipper Bridge Melds Left-Side Drivers With Right-Side Drivers

Hong Kong drives on the left side of the road, mainland China on the right. So how do you prevent crashes when driving between them?

Chinese Flipper bridge

One of the most vexing aspects of traveling between mainland China and Hong Kong is the car travel: People in the former drive on the right side of the road; people in the latter drive on the left (a vestige of the British empire).

So to quell confusion at the border and, more importantly, to keep cars from smashing into each other, the Dutch firm NL Architects proposed a brilliant, simple solution, the Flipper bridge.

Flipper bridge

The bridge does exactly what the name suggests: It flips traffic around. The key here is separating the two sides of traffic, using a figure-eight shape. One side of the road dips under the other, funneling cars that were traveling on the left to the right (and vice versa), without forcing them to encounter head-on traffic at an intersection. The bridge makes what should be a disorienting switch exquisitely easy. Check out PixelActive's 3D model of the traffic flow below:

Say, for instance, you're coming from Zhuhai. As you cross the bridge on the right into Hong Kong, the highway slopes downward to let you pass under the oncoming traffic. As it slopes back up, you reemerge on the left. No cars barreling straight at you. No concrete labyrinth to maneuver through. No sweat (and, ostensibly, no blood).

Flipper bridge

The bridge is part of a master plan NL Architects floated for an ideas competition on the Hong Kong-Zhuhai-Macau Bridge, a complex of bridges and tunnels connecting the west side of Hong Kong to mainland China and Macau. (As clever as their idea was, NL Architects, alas, didn't prevail; first prize in the professional category went to a proposal called "Under One Roof" that unctuously billed itself as "China, Macau and Hong Kong as one big family," all but ensuring a win.)

In some ways, though, perhaps the Flipper bridge may be too good of an idea. One of the great paradoxes of driving, as Tom Vanderbilt highlights in his terrific book Traffic, is that dangerous roads are actually safer precisely because they're perceived as dangerous; that is, they make drivers more vigilant and therefore less likely to get into a collision. (Which explains the seemingly inexplicable appeal of European roundabouts.)

In 1967, Sweden switched over to right-side driving, after years on the left, and everyone steeled themselves for a spike in accidents. Instead, incidents plummeted. Facing apparent peril, people became more cautious behind the wheel (and others probably stayed off the road altogether).

Sure, the Flipper bridge seems like a fail-safe idea. But what if a driver, lulled by the easy left-right transition, forgot that the change over had even been made? You can bet a horrifying accident would result. Sometimes, a little danger is a good thing.

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    There is a problem with this bridge. When you switch over to the other side you move to a fast lane if you were on the slow lane and vice versa. This could be dangerous. 

  • Ska8terboi

    Wouldn't change the lane you were in.... I don't know why people keep saying this...

  • Steven kr

    wait a sec... what would happen if there was a pretty high wave that hit the lower bridge? I think that the didn't think this through...

  • Sean


    What is bleeding here are your arguments. While you obviously did some background research, you missed an important point: the bridge is not only a blueprint, but under construction at this very moment and is well known within the circle. (

    1. "Fair competition": it's obviously what you are implying here, that foreigners don't stand a chance in China. The reality is exactly the opposite: Foreign design firms have monopolized the high-end engineering design market in China, that Chinese designs don't have a chance. Instead of the Dutch, the bridge now adopt a design led by a Danish firm, as outlandish as the firms that have designed the "water cube", the "bird nest", the National Grand Theater, Beijing International Airport, and the Central Television Station.

    2. Bridge as a means to avoid surface crossing (like highway interchanges), it's indeed "a piece of cake". However, it is absolutely novel as a measure to regulate left-driving and right-driving traffic patterns. Feel free to name a precedent if you are so convinced of it.

    3. Economic sense: the travel time over land will be shortened from 4-5 hours, to 30 minutes. The bridge has been 30 years in the making, and spearheaded by well-known private interests. It's not a bridge to nowhere, it's a bridge linking the 2 most vibrant regions in China. For you to prefer a ferry, you might just as well against the Channel-Tunnel as well.

    4. Check points: most tollways have toll booths, would you rather avoid these highways altogether?

    5. Necessity of the "flipper": The bridge is a "Y" shaped bridge linking 3 cities, with Macao contributes and benefits the least from it. (see Wikipedia link provided above). Therefore, some accommodation of varying driving habits makes perfect sense.

  • marcus youngblood

    @ chinkhater the design is pretty accurate for the amount of traffic and as far as your racial slurs they were outdated long ago probably with your ignorance and buckskin clothing i am native american however i do not go around hollering white man or ghost face although since you probably hide behind a sheet this would probably work for you a nickname but instead of try to get down to the backwoods level and make you understand i will just give you some advise to grow up get a life and learn to be up to date the slurs are history you are now in another century

  • Dw

    RE: comment about u-turns - hello! Ever been on bridge? What bridges allow u-turns? Once you are on a bridge, you are committed.

    This is a lovely and very smart design ... and it's just a simulation - no doubt weather considerations and water levels, and especially engineering concerns, would dictate the height.

    And people posting here do not seem to have driven in foreign countries, or know anything about China. The Chinese are now buying cars at very high rate. And their driving patterns are not the same as ours. The "fast lane" comment is particularly lame.

  • John Fink

    yea, not to metion what about monsoon season? and that lower bridge looks lower then hell which means if that water rises it will flood that lower bridge, i got the easyest solition how about hong kong and the other place just both start driving on the same damn side of the road???? its not that difficult one of them can compermise

  • Paz Wright

    It's very good idea showing the drawing to the public and everyone give there own comments how they will like it or not etc, etc. Because other say it's too confusing to the drivers and I agree with that because not all drivers are clever enough to be aware of what's going on around them. One thing more bridges from HK to Mainland are already there and no change or flip and no problem even the driver is from left to right, so why make it complicated?

  • Zsolt Barczy

    This article is bleeding from many wounds indeed. Let me list some.
    1. Ideas competitions in China are never about ideas, and are never a fair competition (as the name would suggest). The "winners" are usually pre-selected well before the tenders, so anyone participating in such games are usually wasting their time/money/energy anyway. So no wonder that the Dutch group did not win. (I agree that the Netherlands has indeed extensive engineering know-how when it comes to water and civil engineering.)
    2. As someone already mentioned, merely avoiding cars stopping and then proceeding on the other side of the road (as it is today) does not really have much added (economic) value. It's not a big deal to stop at the border, as one MUST stop anyway, and then proceeding on the other side of the road. Piece of cake.
    3. It is not clear to me what's the point of this entire construction project? Is it real of fake? If it is real, it must be a stupid idea from the Beijing government, as it is absolutely unnecessary to build such a highway between the three mentioned regions. If someone wouldn't yet know, Macau (the first Western establishment in Asia by Portugal) and Hong Kong (the latter, bigger attempt by Britain) BOTH drive on the left side of the road (and still have the steeting wheel on the right (right: the right) side. Both ex-colonies have a mirror-built counterpart over their mainland Chinese border: Zhuhai and Shenzhen, respectively. These "me too, me too" mega-concrete-cities drive on the right side of the road, just like the US and continental Europe. Currently the traffic is pretty well done between these cities: Macau and Zhuhai has a border, Hong Kong and Shenzhen has one, too, and one can drive from Zhuhai to Shenzhen on land. Between Macau and Hong Kong there is a pretty good jet ferry service 24/7, as well as cargo ships for the rest. I don't see the economic value of wasting billions of yuans/dollars to built a road that is practically useless (no demand for it), albeit similar to the pointless maglev windows-project in Shanghai (the superfast but supershort airport express).
    4. But, let's assume for a second that it would make whatever economic sense. Even then, one CANNOT link mainland Chinese territories to either Macau or Hong Kong without a massive BORDER station. EVERY single vehicle MUST stop and be inspected upon crossing these borders. Hence, it's completely pointless to try to make a "fluid" highway between these entities (mainland territories vs SARs, ie. Special Administrative Regions).
    5. The only (literally) viable alternative could be a linkage between Macau and Hong Kong (the two free SARs), but they are both driving on the same side of the road... so no need for a flip-bridge.
    I understand that today's journalism is suffering from acute sensationalism, but this was a little too much :-)

  • jctbay

    In reference to the issue of whether it should be higher. Pretty sure they took that into consideration and took any preventable action necessary.

    The Dutch are genius on dam, levy and bridge construction. Awesome!

  • John Michael Hoggard

    It looks like a good idea at first, but no one has commented on the fact that once the traffic has crossed under or over , The fast lane becomes the slow lane and there will be a big scramble for the fast drivers to to get into the fast lane that used to be a slow lane and visa versa. How about the large lorries with speed restrictions suddenly finding them selves in the outside Lane . The whole process is fraught with danger as this suffling of lanes commences. The guys in the middle lane are still in the middle lane of course and suddenly find vehicles on both sides attempting to switch. Not good. Mike

  • michael q

    even if they do have fast and slow lanes it wouldnt matter cuz the left lane is the left lane and the right lane is the right they dont change the lanes dont change the side of the road you are on changes

  • Kate

    How do you even KNOW if there ARE fast/slow lanes? That isn't the US. Maybe they don't have fast/slow lanes.

  • Ken S

    guess it wouldn't matter, cause I've been there a couple of years ago, their highway speed is like our local traffic speed. also, it doesn't matter if you're on the fast or slow lane, the way (mentality) those people drive over there don't really have that much of a speed variations than here in the states. a slight indication on the road to should the fast and slow lane could probably solve the problem easily, but you've mentioned a good point, this is something they should concern about.

  • Iago Expando

    It is true in many countries (but I'm not sure about China) that the lanes on a multi-lane highway are not classed as "fast" or "slow" but "regular" and "overtaking" lanes. In a three lane system the side closest to the opposing flow of traffic is the ultimate overtaking lane if the other two lanes are fully utilised already.

    It is also true that in those countries with regular and overtaking lanes that drivers must - and, indeed, do without too much difficulty - drive with a lane discipline that might seem alien to most drivers in the USA.
    It's true that most US drivers are accustomed to other traffic on whichever side they feel inclined to, unless lane discipline is explicitly controlled by signs. And even then, frequently not.

  • Dhruv Singh

    Well this is definately a good idea, but there is a fair chance that this is not novel as of today. I know of designs based on the same concept and some of them has patent filings too.The public attention given to this design is surely going to attact the patent/copyright owners to react.

  • marco

    "Which explains the seemingly inexplicable appeal of European roundabouts"

    European roundabouts cost FAR less to install (no lights, no sensors, no power, no wiring, etc.), cost FAR less to maintain, and 98% of the time are MUCH faster than a traffic light system. So it's cheaper and faster by far with the only requirement that you have to use your brain rather than sit and wait at a red light (hardly a downside there ...). What's inexplicable is how the author seems to be completely unaware of this (and btw, I'm not European ...)

  • Flax Seed

    Two factors are critical to whether a roundabout (aka rotary) is a good solution.
    The size of the roundabout, and the speed of the traffic entering and traveling in the roundabout.

    In Massachusetts, around Boston, rotaries are exceedingly small and the cars entering them and traveling in them drive extremely fast. Those facts when combined with aggressive drivers and drivers who don't comprehend that traffic in the rotary has the right of way produce a LARGE number of accidents.

    I've seen rotaries work well out in the suburbs where land is plentiful and there aren't a lot of cars on the road. That's great. However it's clear to me (and other Mass. residents) that roundabouts/rotaries cannot be considered a viable solution everywhere.