books that give off that ‘stranger things’, occultish, ‘something is in the woods’ vibe

hi, i’m looking for a book written about a person or group of people who essentially starts having weird things happen to them in their day to day lives out of nowhere and it all leads back to something being like in the woods or something similar.

being from the adirondacks i really like horror that takes place in the mountains or forests like we have here because it’s so much easier and more fun to visualize.

bonus points if the book includes a cult or some weird demon / THING that’s following the main character around.

i’m not too strict on these rules though so please recommend also your favorite general ‘something is wrong / in the woods’ books !!