I'm running a https://velomapa.pl - website with cycling related stuff (routes, races, photos, and other stuff) in Poland.

It's a super seasonal niche. During the season it brings around $1000/month through various types of ads and donations.

Now, I'm building and growing https://travelermap.net, which hopefully will work nicely all year around. It's also a content site that I'm planning to monetize using ads.