Trekking in Russia similar to Kungsleden

I am afraid that you won't find a similar infrastructure (well-tended cabins spaced out along the well-marked trek, or at least a well-marked path long enough for multi-day hike) anywhere in Russia. Anywhere that is reasonably picturesque, at least. Casual multi-day hiking is simply not popular enough here; it's generally assumed that people going on long hikes should possess adequate pathfinding skills, set their own tents, find water, etc.

As a foreigner, you'd be better off hiring a guide: there are plenty of companies providing guided tours near Baikal, some of them should have English-speaking guides as well. Not to be too alarmist, but going on your own might be dangerous because Baikal weather may change fast, leaving you stranded behind a flooded creek, mobile coverage may be poor, limiting your ability to call for help, and you can't completely discard a possibility of conflicts with locals, which an experienced guide would mediate.

I've only been personally in Baikal region, but I'd assume that the same applies to Altai (I heard that they offer wonderful horse tours there) and Kamchatka (BEARS!).

This is a partial answer; I hope an expert Russian wilderness explorer can come up with a more comprehensive answer.

English language information about Russian nature is very limited. I am not aware of a trail with as high use and staffed and equipped mountain huts as Kungsleden, but there are wilderness huts in certain regions. The Great Baikal Trail is somewhat famous but I don't know what the infrastructure is like.

I'm currently learning Russian because I'm planning a trip to Europe's largest national park, ???? ??. The park is right on the border with northwestern Siberia, in the extreme northeast of Europe. I got hold of an overview map for the northern half of the park. The map shows a number of cabins, some named, some unnamed, along the route from ?????? to ????????. I have not been there and I don't know the situation, but based on blog posts I have deciphered, the trail is so rarely used it is essentially absent, and the cabins are basic wilderness cabins with neither staff nor provision. I have not found any photo or information from the inside.

Some photos I found:

• Here is one photo of a location that has a cabin marked on my map. I'm not sure if that roof is waterproof!
• Another one

Some posts including photos of the larger area:

• https://pikabu.ru/story/turisticheskie_mesta_respubliki_komi__natsionalnyiy_park_yugyid_va_4177164
• https://www.liveinternet.ru/users/ferinae_flamma/post376799670/
• https://af1461.livejournal.com/2006/08/

If my trip happens I can report back in the second half of September!

You can find marked trails good for multi-day trek in Crimean mountains, starting from Angarsky pass. Local trekkers community maintains campsites, springs and marks trails. You are still expected to have a tent on you to make use of those campsites.

I imagine that mountains regions near Dombai and Elbrus may have similar level of infrastructure.