Villa del Trebbio is really ancient, but in 1428 Cosimo de’ Medici completely renovated and enlarged it; the architect is Michelozzo (the same of Cafaggiolo and Palazzo Medici).
This villa was surrounded by forests and agricultural estate, and even if it looks like a fortified castle, it was a place of pleasure and rest for the Medici family. Today the castle is surrounded by a beautiful cypress wood with more than one century old trees.
Unfortunately today this villa is private, and visits can be booked just in some special occasions.
You can see the tour of my daytrip in Mugello in this post!