Ask HN: What are your favorite personal, topic-centric websites?

I have a very fond memory of "specialty" websites that were halfway between a personal blog and encyclopaedia about very narrow (and somewhat random) topics.

They were/are mostly maintained by a single person or small group of people who often have very little clue on how to make a website.

Between social media and big commercial websites I have seen a lot fewer of them in recent years. What are your favorite?

Examples:

A website about diamond willow stick making: http://www.sticksite.com/

A great resource about everything around rock tumbling: https://rocktumbler.com/questions.shtml

A wonderful website for learning piano: https://piano-ology.com/