Akira's post-apocalyptic - Neo Tokyo was wiped out long before the story starts.
So's Yokohama Kaidashi Kikou. Everything is in ruins. The sea has risen at least 50 feet.
And if you think these are too happy, there's always Ai-Ren, which is both post-apocalyptic and everybody dies by the end (it's great, though - well worth your time).