Hi, I was wondering how people would time a 1 hour meditation session without setting an alarm on their phone.

I don't really want to keep my phone with me during meditation, but I do want to have a way to notice it's time to stop.

People somehow managed this in the past before phones existed right? So what would be a good way to do this?

I've put incense-timing into practice since posting this. It works well, because at the end you can smell the wooden stick burn. I don't have an especially good sense of smell, normal, and I can tell easily.

Nice, great to hear it works for you!
What type of incense do you use? Is it japanese-style incense?

I looked up 'Japanese-style incense' and I see pictures of sticks standing in sand.

For what I'm talking about, it has to have a wooden stick. The ones I have are made in India. When it hits the transition point highlighted below, and the wood starts to burn, that's quite a distinctively different smell.

The other advantage is that the time is really consistent (within one brand anyway). Every stick will burn at 50 minutes for one brand I checked, 45 minutes for another, with very little variation.

Yeah, I think all the incense sticks that i've used are with a stick.
The reason I asked is because I have some indian incense at home and when they burn, the smoke stings my eyes. So I have to ventilate well, but then I don't smell much anymore.

Supposedly, the japanese incense (more specifically Kōdō incense) is supposed to burn cleaner and have less strong smoke. They are usually also very consistent.