Please help me find this story

Hi, I'm looking for a specific story that I've read years ago. It might have been on fanfiction.net and I'm pretty sure it was Snarry

It starts with an accident during a lesson (Severus is the professor who's present). Harry disappears, but re-appears a few moments later, albeit an adult. He's spent years in the past with the founders (I think Salazar acted as his father and at one point even arranged a marriage for Harry?).

Hope someone can help me find it and that it's still available somewhere.

Thanks in advance!