[kalenx]

Setting up a cycle lane in place is cheap, but not easy (at least in North America, people will always complain about the "war on cars").

Also, setting up a good cycle lane can be more expensive than you think. If you have a nice bike lane that spreads over 5 km but there's a 200 meters gap in it because of a bridge which was too narrow to keep the bike path, then you don't have a nice lane at all.

[BitwiseFool]

I've never understood why bicyclists can't just use the sidewalk for most of the commute. I get that it becomes impractical in dense areas where people are actually walking but most of the roads I travel along have vacant sidewalks.

[vinay427]

Assuming we're not talking about the extra-wide sidewalks common in city centers which sometimes also host designated bike lanes, ordinary sidewalks that I've seen throughout the US and Europe are nowhere near wide enough to fit even a single cyclist passing alongside a pedestrian without a risk of collision. Add multiple pedestrians walking alongside each other, other hazards such as parked cars, less competent cyclists such as children, or pets (on or off leashes) and it quickly becomes a recipe for disaster for one or both of the sidewalk users.

Also, bicyclists in cities tend to travel closer to the speeds of cars than pedestrians, and tend to have more similar dynamics such as turning radius and stopping distance which infrastructure for cars is already designed around. Additionally, car drivers are licensed and there is an expectation of awareness that they must exhibit. This makes it far easier to place slower-moving "hazards" in their path than adding faster-moving vehicles in the path of pedestrians.

[estebank]

On top of everything else mentioned in the sibling comments, riding on the sidewalk is illegal in many locales.

https://www.sallymorinlaw.com/bicycle-accidents/riding-your-...

[dmm]

The most dangerous part of a sidewalk for a cyclist are places where they intersect roads. Drivers just aren't expecting sidewalk users moving at bike speeds.

Some areas have long stretches of sidewalk without intersections those are fine for cycling assuming they have little pedestrian traffic or are wide enough to pass safely.

[BitwiseFool]

This is pretty much my conception of when cyclists should be using the sidewalk instead.

[dmm]

Another thing to consider is that in many areas it's not legal for cyclists to use the sidewalk.

Most sidewalks aren't appropriate for cycling. The exceptions I was describing are mostly found in big commercial developments, target, walmart, etc. Around me they tend to build wide sidewalks, well separated from the busy road. Here's an example:

https://www.google.com/maps/@38.9146941,-92.3196647,117m/dat...

But most sidewalks aren't like that they are crossed regularly with driveways and end at a road every block. Every driveway is dangerous because drivers just don't look for people moving at bike speeds(2-3x faster than a pedestrian) on sidewalks. I personally know two people hit while cycling on a sidewalk because somebody pulled into a driveway and didn't see them.

Imagine you're a cyclist, on the sidewalk, trying to cross a four-way stop. If you cross at the sidewalk, you're at extreme danger of being hit by a car making a right turn. This is called a right-hook.

The road infrastructure in the US was built without consideration for bikes and so it's really annoying to many drivers when cyclists use roads but that doesn't mean the right place for cyclists is on the sidewalk.

[souprock]

OK, I'll imagine I'm a cyclist, trying to cross a four-way stop. When I was a teen, I used to do exactly that, riding my 10-speed on the sidewalk. This is how it goes:

Approach the intersection, coasting and then braking. Come to a stop, with feet on the ground. Optionally, dismount. Wait for a big gap in the stream of cars. Walk or ride across the intersection, remounting as necessary, and then continue on riding.

I'm not seeing the extreme danger here. It's not possible for a car to make a right turn because there isn't any car. The cyclist doesn't cross until the cars are gone.

Urban adjustment: there might be a "walk button", and there is a chance that it is actually connected to a traffic signal. Cross only with the walk indicator active.

I don't see any reason why this should be illegal. It's far safer than the alternatives.

[dmm]

> Optionally, dismount.

For sure, one of the advantages of cycling is that you can at any time become a pedestrian by dismounting. This allows you to take advantage of pedestrian crossings. It's going to be really annoying to dismount at every intersection or every ~500ft/155m.

> The cyclist doesn't cross until the cars are gone.

There's a four-way stop by my house that continuously has traffic for a hour twice a day during rush hour.

> remounting as necessary

A key to road safety is behaving in a predictable manner. Cars are supposed to yield to pedestrians at crosswalk but bikes are vehicles.

It's far safer at the intersection to merge into traffic, take the lane and yield the intersection with the same rules as other vehicles.

> It's far safer than the alternatives.

History shows it's not. Sidewalks aren't designed for use by vehicles going 3x the speed of pedestrians.

It's not safe for the pedestrians and it's not safe for the cyclists.

[Johnny555]

These are also the areas that work great for bike lanes, a nice uninterrupted stretch of bike lane without cars turning into them.

[bluGill]

Cars and bikes mix better than bikes and walkers. Which is to say not very well. Walkers move in unpredictable ways and freeze when a bike is heading at them. Bikes move more like cars - they get a bit better handling, and are not as fast, but overall they act like cars.

I wouldn't want to bike when there are many cars in the same lane as me, but it is still safer than biking on sidewalks where are many pedestrians.

[dfgdghdf]

* It's illegal in most countries

* It tends to be busy with pedestrians (not everywhere, as you mention)

* It's not safe when crossing side-roads

* It's inefficient if you walk at junctions

[obmelvin]

Riding on the sidewalk is dangerous. Cars do not look for you when moving between the street and a parking lot/driveway/etc.

I have had more close calls with cars riding on at most 10 miles of sidewalk (and that's being generous to be honest) in the past decade than with ~6000mi riding in the road.

[acrispino]

In some places it is illegal to ride on the sidewalk.

Also, the width and amount of obstructions on sidewalks varies widely.

[stfp]

You should try it?

[BitwiseFool]

I used to do this all the time growing up. But I assume times have changed because it's illegal now.

[EdwinLarkin]

Depends how walkable the city is.The more walkable it is the more people you will see on the sidewalk.Sidewalks are for pedestrians not for fast moving vehicles.

[jtdev]

You know how many in the cycling movement view automobiles as being fast, dangerous, machines clogging up the roads? Many pedestrians view cyclists as a similar fast, dangerous (often rude and inconsiderate) presence on the sidewalk.