The site this banner links you to seems to be ded: https://nashikouen.net/
The Heyuri wiki even says so: https://wiki.heyuri.net/index.php?title=Nashi_Kouen

Do we just take down banners that lead to ded sites, or do we leave them up as mementos? On the one hand, it's a bit sad to throw out a perfectly-good banner, but on the other side, it'd be a bit morbid if, as the years pass, a lot of our banners turn from advertisements to tombstones: "Here lies Nashi Kouen. It was a neat site"
Though I'm not actually worried; I was just curious enough to warrant discussion.