Yes, you can! These are official bike routes. From the south arrives there the EuroVelo 5* and 12** (blue-red). The red dots are regional and the blue (if you scroll further in) the local bike routes.

This is what makes ct so beautifully clear

* https://en.wikipedia.org/wiki/EV5_Via_Romea_Francigena

** https://en.wikipedia.org/wiki/EV12_North_Sea_Cycle_Route

Thankyou, priceless, I did post a thankyou, it hasnt appeared ❤️

Worth noting there’s a map key you can call up too – it’s not 100% complete but most of the stuff is there. Look in the corner of the map for the ‘Key’ link.

Thankyou, I did your route today, fabulous, sunny spring day,medieval town to medieval city pilgrimage, hardly a car passed me, joyous day thankyou❤️🙏

How about other types of dots, like the smaller blue/gray ones south of Canterbury on the map above?   Or those south of Eastry?   I keep consulting the key in cycle.travel but I really struggle to line up what I see on the map with the symbols and colors in the key sometimes.  I'm not sure if it's my eyes, or my screen or my brain.  I'd really like to be able to make the most of the info that the map provides.

Or those south of Eastry?

Just taking that as an example, the blue dotted line suggests that it is a regional route. I think the difficulty in seeing the detail is that the underlying road can vary as the route goes along. Through road, trunk road etc. all have different colours. It may help to swap between the map styles to get a different perspective.

It's labelled "15" (sometimes there's a name) and a quick Google can throw up some more info. A handy hint is to click on the route to add a viapoint and see if a name pops up in the dialogue box. It was discussed here: https://cycle.travel/forum/thread/5148 

However, in unfamiliar areas it can be very confusing. Most EuroVelo routes for example are an amalgamation of lots of local/regional/national routes to create one international route. It's beyond my poor brain to figure out how to accurately (and usefully) represent that on a map.

That's on top of different standards from province to province, never mind country to country! Cycling between towns in the Netherlands is rarely on roads, instead on dedicated bike paths that may or may not be along the road. In most of the UK cycling between towns is on the road, I believe. The Vennbahn, a relatively short Rail trail, involves three countries and various provinces. The signage changes along the way reflecting those changes, the map doesn't.

A good tip is to click on the route and use "Streetview". To be honest, that will give a far more accurate idea of what the road is like than any dots on a map.

My understanding is that "Cycleways" are dedicated, traffic free routes. There, the surface information can be more fickle, depending on where you are - and the weather! As an example, CT will direct me off the  Via Verde de la Campiña, south of Cordoba Spain. A rail trail, dedicated to cyclists, hikers and horsey folk that might seem like overkill until heavy rain turns a section to thick, sticky mud. Closer inspection shows that the whole VV does not have the same surface information. On a bright, sunny day after previous bright sunny days CT is being very conservative. The day after heavy rain? Not at all.

It's probably worth remembering that just because a map suggests that there is a bike route of some kind there is no guarantee that that is the best way to cycle from A to B. Sometimes that bike route was made long ago by people (or worse - a committee of people) who seem to have had little knowledge of cycling. Sometimes, some local enthusiasts for self flagellation have managed to create and show their own perverse routes. They'll show up as Local or Regional cycle routes on the map. It's a hardy soul who will tackle them! :-)

Worth noting (as Hobbes alludes) that c.t’s route choices don’t unthinkingly follow the signposted routes. Sometimes, when you plan a route, it will diverge for reasons of directness, surface quality, traffic levels or whatever. For example, I just tried a route from Reading to Oxford and it took me on country lanes to avoid a long dog-leg via Abingdon and Didcot – nothing wrong with the official route but it’s about four miles longer. But you can of course drag back onto the official route if you want to go that way.