DS, I think this may be less about elevation and more about how CT works - using a variety of data (of which gradient or elevation is only one part.)

Actually, I know that elevation plays a part in calculating the route but I'm not sure of the role of gradient.

In any case, the suggested route portrays all the characteristics of CT that I am familiar with - it is avoiding an urban area in favour of more rural one and is including a motor traffic-free stretch. The elevation is actually less (by 20 meters) on the unedited route. although the max gradient is slightly higher (3,5%).

By the by, have you actually measured the elevation and climbing on both routes? Personally speaking, the numbers for both routes are what I would place within 'the margin of estimation'. Personally, elevation/gradient would not influence me to choose one of your options over the other. In my experience, Max Gradient is very much a guideline and not to be paid too much attention to. Sure, it suggests a bit of deeper looking at the elevation profile but not much more. 

I'm guessing that you are familiar with the area to be able to reduce the gradient by going so (relatively) far off route? In that case, you're using CT in possibly the optimum way - adjusting the route based on local knowledge and preference. 

Preference is a tricky thing, especially when they can change for the same person over the course of a day. 

If you haven't read them these links might be interesting:

https://cycle.travel/map/difference

https://cycle.travel/advice/map/faq

If you're not aware, choosing 'paved' will give another option as will 'Find Alternative' both of which have a lower Max Gradient than your original. 

Hi Hobbes, thanks for your response.

I am actually new to the area and to cycling up hills, which is why i prefer maintaing a steady gradient of 5% which for now, seems to be a gradient i am comfortable cycling uphill for fairly long distances. I haven't tried anything higher than 5% but i hope to soon. By the way, when i say 5% i mean the number that pops up as i hover my mouse along the elevation profile on the website. i tend not to look at the maximum since it's usually misleading.

I did another route today, and had to again re-route to avoid steep gradients. This is the route c.t suggests: https://cycle.travel/map/journey/579011 and this is the one i ended up taking: https://cycle.travel/map/journey/579012

My route is a 150m climb on the website and a 199m climb on the iOS app while the default c.t routing is a 130m and 185m on the website and iOS app respectively. Well, i wasn't expecting that and i honestly don't have an explanation for it 😂

My feature suggestion would be an option to 'avoid steeper gradients' so that c.t could take me on longer, higher routes but through less steeper roads (as much as possible).

I do think real life measurements can be way higher than whats shown in the app, unfortunately i don't have exact numbers to share as i frequently tend to take the wrong turn because i misheard my phone's speaker at high speeds 😅. I don't mind climbing higher than whats shown in the app, i just don't prefer really steep climbs (for now, hopefully).

have a good one,

ds

I did another route today, and had to again re-route to avoid steep gradients. This is the route c.t suggests: https://cycle.travel/map/journey/579011 and this is the one i ended up taking: https://cycle.travel/map/journey/579012

DS, both of those routes are the same. However, this is the most interesting:

My route is a 150m climb on the website and a 199m climb on the iOS app while the default c.t routing is a 130m and 185m on the website and iOS app respectively.

The fact that the app is calculating a different elevation to the website. Admittedly, it's a short journey. 

 My feature suggestion would be an option to 'avoid steeper gradients

Unfortunately, the degree of personalisation is limited. The first entry in the FAQs will explain more. https://cycle.travel/advice/map/faq

The apps don’t yet have the latest updates to the elevation calculation algorithm that the website does, which is why the figures are slightly different. It’s easier to update the website than the apps (because every new version of the app has to go through Apple/Google review, which can be slow), so I tend to experiment with the website and then port across to the apps when it’s stable.

Hobbes is spot on as ever – unfortunately each additional routing mode means renting extra server space (which costs £££) so it isn’t really feasible.

In the initial route it’s optimising for low traffic at the cost of a short steep climb. I’m actually slightly surprised it doesn’t choose Mayfield Road which looks like the best of both worlds – less of the 9%+ climb and still low traffic throughout. If I have the proverbial spare minute I’ll look into that.

Slight word of caution on “real life measurements” – you can get these by manually totting up results from a real barometric altimeter or by counting the contours on an OS map. Anything else (including anything reported by most GPS units and phone apps) is just the interpretation of some software, and not necessarily any more or less accurate than what c.t is telling you!