Margaret's Castle is a small Tower house probably built in the 15th century. Only two storeys still exist but there is evidence that it was at least three storeys high. It is vaulted above the ground floor with a rectangular tower with projecting turrets in the north west wall. The doorway between the turrets was protected by a murder-hole. A spiral stairway rises within the west turret.
Ardglass had at least six castles and remains of four of them can still be seen: Ardglass Castle, Cowd Castle, Margaret's Castle and Jordan's Castle.
References:The stone church of Gamla Uppsala, built over the pagan temple, dates from the early 12th century. Due to fire and renovations, the present church is only a remnant of the original cathedral.
Before the arrival of Christianity in Sweden, Gamla Uppsala was the seat of Swedish kings and a ceremonial site known all over northern Europe. The settlement was home to royal palaces, a royal burial ground, and a great pagan temple. The Uppsala temple, which was described in detail by Adam of Bremen in the 1070s, housed wooden statues of the Norse gods Odin, Thor and Freyr. A golden chain hung across its gables and the inside was richly decorated with gold. The temple had priests, who sacrificed to the gods according to the needs of the people.
The first Christian cathedral was probably built in the 11th century, but finished in the 12th century. The stone building may have been preceded by a wooden church and probably by the large pagan temple.