Yep. It's clear that Google Maps optimises for city riding and that's cool, but it does fall down badly on longer tours. To a large degree this is inevitable - only OSM actually has the level of surface quality information required for this sort of planning.
With my site, cycle.travel, I've taken the opposite tack: generating quiet, safe routes for leisure and touring rides, while still being as fast to generate routes as Google Maps. Sure, I want it to be usable in cities but it's not the main focus.
People have used it successfully to plan month-long tours across Europe and the US. One of my favourite bits of feedback was https://www.cyclechat.net/threads/swindon-to-orkney-a-wet-we... , where someone just punched in a start and end point at opposite ends of the UK, and rode the route it suggested without any tweaking.
https://cycle.travel/map if you want to play - always happy to hear suggestions/feedback (and thanks to Jake for including it in the post!). Currently Europe/North America/Australia/NZ only.
I believe that even in the city it simply maps a path as suitable for cycling and that's the limit of the optimization. It then becomes a "shortest/fastest trip" calculation. They don't mark roads and paths for specific types of cycling and you're not asked to provide such info. So whether it's asphalt, cobblestone, or a dirt road even in the city it will make no difference as long as it's suitable for some bikes. Found out the hard way a couple of times...
At first glance your site shows the local "cycle highways" which is really cool. However I accidentally clicked on the map twice while scrolling around, and then couldn't figure out how to clear the route so I had to reload the page.
On closer inspection I noticed a button called "close route" which seemed to do what I wanted, but I'm not sure if it has other side effects
I do agree with 'overlordalex' on the 'Close Route' button. I couldn't find it at first and 'close' seems like a weird verb to use for 'clearing' the current route. Unless I am misunderstanding what the button is supposed to do. I would personally have a 'Clear' button somewhere close to the 'Get route' buttons (but then again I am no UI/UX expert :)).
Can I get the distances in km instead of mile?
For example, one of our local highways has a speed limit of 55mph and a shoulder that is maybe 10 feet wide with a rumble strip near the cars. Is that a good road for bicycles or not? I'm OK with it but some of my riding friends are not. A bike path can be perfect for a family yet dangerous for practicing time trials.
I've also been surprised at how narrow some of my favorite roads are for driving. Just about any road is great if it doesn't have traffic. So a good road at lunch time is no good during rush hour.
So maybe the ultimate bicycle router would a) Offer a bunch of preferences just like you see for cars, e.g. "avoid freeways", "avoid tolls". b) Flag roads as "avoid", e.g. that four lane road with no shoulder next to the sidewalk. c) Specify roads with gravel. (OSM data can have this; not sure about Google.)
I know they do a lot with determining routing based on what other cyclists prefer, but I'm not sure how granular it is.
Even in cities Google is similarly terrible, and it's actually gotten worse over the last few years as more unsuitable routes are listed as "cycle paths". I was trying to get home through London and Google sent me about a km in the wrong direction so that it could route me onto a muddy canal bank. I found myself wishing that I could simply put it in car navigation mode but avoiding routes that aren't legal for bicycles, but that's not an option either. E.g. from Great Dunmow to Bishops Stortford, all you need is to go straight down the old Roman Road, but there's no setting for Google Maps that will send you there: in bicycle mode it sends you down a muddy track, and in car mode it sends you down the A120 where bicycles are legally banned.
(Not to mention that here in Japan it simply refuses to provide cycling directions at all).
It's just not good enough, IME. It's well worth taking ten minutes to install OSMAnd and get decent directions instead.
These apps should also let you export/import gps data, which Google does not do.
For simple directions around town I agree that Google Maps is good enough, but as soon as you're beyond riding just to get from point A to B, it's nice to have something more.
Note: some bike computers also have built-in mapping, something I find useful on my Garmin Edge 530 is the breadcrumb feature which allows me to explore new territory to my heart's content and not worry about getting lost as I can just turn around at any point and follow the breadcrumbs on the map.
Note 2: I don't even have my phone out, it's always in my under-seat bag. Cycling computers are great, battery lasts forever (well in excess of 10 hours of riding with the computer on), visible in all lighting conditions, show a plethora of data at the same time (I have 8 live metrics shown at once), and are mounted in such a way that if you fall they likely won't get damaged, because a) they're unlikely to take a direct hit, and b) aren't big & heavy like a $1k iPhone 11 Pro Max with lots of glass that can shatter.
It also didn’t understand the impact of hills, which is why I cut the attempt short (1080 km) after it redirected me up a Swiss hill instead of keeping me close to the Rhine.
I would’ve preferred a GPX to follow, but I couldn’t find any of that route.
(Also, it's well-signposted, and in any case the whole point of the route is to follow the biggest river in Europe, you don't need a lot of navigational aids).
I took a wrong turn in Eiken, which isn’t directly next to the river, and didn’t notice my mistake until I’d already exhausted myself. The nice scenery was a pleasant but unfortunate distraction.
This is unacceptable given that cycling the wrong way is illegal and dangerous.
The US in San Francisco, where cycling against traffic is illegal.
A few years ago, following Google maps cycling directions me and a couple of friends on road bikes were led through muddy forest trails, old rail road tracks and green lanes on a London -> Paris <24hr attempt (we took 26hrs).
The difficulty with cycling directions is that there's not a 1 size fits all solution, a roadie needs smooth road but would prefer it quiet and scenic, a mountain biker would rather those trails we found and a commuter/hybrid would be fine on those in short bursts but probably prefer the speeds of the roads.
If I'm doing something of an "epic" route these days I'll spend a bit of time trying to find a suitable GPX that I can sync to my watch for directions - usually that'll come from Movescount, OS maps, Garmin or just someone's blog of a route. For most other things, Google maps works fine.