There are gradations in there for the three different types of twilight

That's helpful, I'll take a look, thanks

I put the location above it when I print posters. It also changes east to west, although the length of the day would be the same.

True, although there's a reasonable level of symmetry about noon

When I print them as posters I put a title at the top with the year and location. The time is then in local time and the hours are there if you zoom in

In short, Daylight Saving Time. It would look neater without it

I haven't got it set up to generate them on the website (yet), I make each one with a semi-manual process.

I feel there are enough examples on the website that you can get a good idea of what you're getting.

Yes, and actually you can choose to show it like this or to have the scale change instead (after all the sun doesn't really change, it's just our clocks).

See the images on the design page of my website to see what I mean.

I don't know that there's a specific name for it. A linear one might be called a sun graph, but I see this more as a type of calendar.

This one is New York City, but I actually created a program to make them for anywhere in the world (and have posted a few examples in reply to other comments).

You can check out some examples for a few other places on my website.

Not quite perfect concentric circles, but a lot closer: https://imgur.com/a/DA3ehYR

It really messes up visualisations like this, doesn't it?!

Here's London without the jump (and changing the scale instead).

One of the options you can choose on my website is whether or not you want that jump to appear.

Precisely, I think it would look much better without that.

Here's London without the jump (and changing the scale instead).

One of the options you can choose on my website is whether or not you want that jump to appear

Not sure where you are, but it does vary a lot, here is Edinburgh for example.

There are also more examples on my website.

After several of my friends saw mine they suggested I sell it, so I set up a website to do that and I'll make you one, wherever you are in the world https://sunlightcalendar.com/

Should have said, this is for next year (2023). With this year being nearly over it makes sense to start thinking about a calendar for next year.

My comment isn't showing yet, but I used Python and the Astral package to calculate the sun and moon times, and then it's basically a (complicated) dot to dot between those times.

I was inspired by things like this visualisation which is equal area, but having always visualised the year as a circle I wanted to combine the two.

Well this is New York City, so depends on your definition really

I created a circular calendar to show the sunrise and sunset times (as well as the times of the three types of twilight and solar noon) and visualise it in a circle. This one is for New York City.
Inspired by things like this and having always visualised the year as a circle I combined them and personalised it for my location.
I used Python and the Astral package to calculate the sun and moon times.
Having made one for myself, loads of people who saw it suggested I sell it, so I set up a website where you can order a printed custom one of your own: https://sunlightcalendar.com/