Taken from somewhere else, seems interesting.
A review from someone else:
"Wow wow wow, I just finished reading the Ever Upward series. What an absolutely wonderful and magical fic series.
The quick gist is Harry runs away from the Dursleys around 8 years old and is taken in by the Basilisk under Hogwarts. He spends the next years secretly exploring the castle, the forest, the lake all while making friendships with the beings he meets everywhere he goes and getting hilariously tangled up in inter-species-nation affairs. As time goes on Harry becomes a pivotal point of revolution for the rights of non-wizard beings.
First off: I cannot speak highly enough of the magical world building. More so than any author (including Canon) I have never gotten so caught up in the places that Harry travels and the creatures and beings he meets there. Especially so in his journeys deep into the forest, I can only describe it as magical. There is such an intense feeling of wonder and awe that carries out of the text. The systems and conventions and languages the author creates for each nation of beings feels fleshed-out and authentic.
The other highlight and really the core theme of the book is Harry's friendships he builds throughout the series. I don't want to spoil anything but this fic did something that few others I've read have done, which is make me care about every character in a massive cast. Each one feels unique and individual and Harry's relationship with each of them is so genuine and charming. The characters are all just absolute joys. Canon characters are written well.
The story itself is very far from canon while not feeling out of place in the HP world. There are some classic canon beats but even those get a very fresh twist. Some characters definitely act out of character but they are eased into that over time.
Take heed of the "queer themes" tag as it gets very queer prominent as time goes on, especially the final 2 books. There's nothing graphic, it makes sense in the plot, and it's much less ham-fisted than fics I've read like Lack of Lamb Sauce but be aware if that's not your cup of tea.
I think the peak of the series is somewhere in the center when Harry is just getting to go on adventures with his friends and things are less politically complicated. It's not to say that the rest drags on or that it's poorly written. It's just that the early wonder and adventure is so well done it always had me excited when the author returned to those kinds of things for a quick break later on.
Absolutely wonderful fic series. Easily Top 10 for me, probably Top 3."