The Bethlen Castle from Sanmiclaus is a representative construction for the late Renaissance from Transylvania. It was built between 1667 and 1683, by Bethlen Miklos, being the place where his daughter married with the baron Kemény Zsigmond, in 1719. The castle has a quadrate shape, built on 2 levels. It forms one compact building, without interior court.
The main facade is oriented to the South and is remarked by the double loggia. The beauty of the castle also has to do with decorative elements from the doors and the windows, of the rooms from the deck-floor, having half cylindrical arches. The building was defended by a wall with 5 bastions and a water ditch.
In 1856 the castle became property of the baron Brukenthal, that made renovations and founded here a school. During Communism the castle became property of IAS. The castle hosted in this period the families of the engineers from Sanmiclaus, becoming afterwards a Kindergarten, prison, canteen.