A few recent examples of dreadful cycling infrastructure design in Britain all seem to have something in common. They’ve been built in ways that we would never design a road for motor vehicles.

We wouldn’t build a road for motor vehicles that had trees seemingly at random in the middle of it.

The Hackney Cycle Superhighway Forest. Cyclist seems to be trying to work out what to do https://t.co/iRBxU54Xot — Mark Treasure (@AsEasyAsRiding) April 4, 2016

No, we would build a road with trees… at the side. Because a road with trees in the middle of it isn’t very convenient, or safe. Nor would we install advertising display boards in the middle of a road.

Anyone got a bulldozer they can lend @CycleSheffield? They need help to remove this from cycle path. pic.twitter.com/ajJKwPNIlz — Matt Turner (@MattTurnerSheff) May 13, 2016

We wouldn’t put zig-zag barriers across a road where it meets another road; zig-zag barriers that drivers have to slalom through before they join the main road.

No – the road would just join the other road normally, and we would trust drivers to use their eyes and follow the markings on the road.

Let’s say a road has to cross another road, on a bridge. Would we put zig-zag barriers on the ramp of the bridge, to slow drivers down because, frankly, you didn’t design the bridge to be driven across at a reasonable speed?

No – we’d built the road smooth and straight, without barriers, and with an appropriate design speed. Because zig-zag barriers are inconvenient, annoying, and actually impossible to get through for some users.

When a road crosses a side road, we don’t expect drivers to cross some tactile paving, entering an ambiguous ‘shared’ area with pedestrians, that loses priority at the junction.

I made a video of Platt Fields north bound (1/n) @SavageHoutkop pic.twitter.com/yh83CGjuiY — Katy Holliday (@KatyHolliday) March 31, 2016

No – we design the road so that it crosses the side road with clear priority, because it’s a main road.

When a road has to change direction, would we build it with sharp, angled corners?

Why is so much cycling infra designed with ridiculously sharp angles? I see this in pics from many different places. https://t.co/r1lvYvtUMm — The Alternative DfT (@AlternativeDfT) February 27, 2016

No – where roads have to go around corners, or have to change direction, they do so in smooth curves. Because vehicles make turns in curves.

Would we ever expect drivers to get out of their cars and walk along a pavement for a bit, because we couldn’t be bothered to create an actual joined-up route from A to B?

How does Bikeminded recommend you cycle down Kensington High Street then? It, er, says you should dismount! pic.twitter.com/yZCyplZNZS — Alex Ingram (@nuttyxander) October 14, 2013

Would we ever build a road, or a motor vehicle lane, that simply came to an END?

No, that would be ridiculous. We don’t expect drivers to simply give up; we build lanes that go somewhere, that don’t just come to an abrupt halt.

Would we ever ban driving completely on a road if a small minority of drivers behaved in an antisocial way? Of course, we’re quite happy to do this with cycling, on the basis that inconvenience is something that ‘cyclists’ should naturally expect to put up with.

Would we cram driving and walking into the same space, either on busy routes, or through junctions?

No – we don’t build ‘shared use’ routes, or ‘Toucan crossings’ for motoring and walking, because that would be inconvenient for driving. We give motoring its own clearly distinct space, with footways for pedestrians, and separate crossings.

In all these examples, the basic design principles we would employ when designing for motoring are jettisoned. Cycling is something that can be bodged in with walking when things get too difficult, something that can be abandoned, obstructed, banned, in a way that we never contemplate with motoring.

When it comes to designing for cycling, a basic rule for discerning whether you are doing a good job is to simply ask whether you would design for motoring like that. If you wouldn’t, then what you are building is almost certainly not fit for purpose.