The Temple of Neptune was erected on the Poreč forum in the 1st century. It is thought to be the biggest in Istria, although only a portion of its walls and the foundations have been preserved.
During the Antiquity, Poreč as well as all Roman towns, had a forum, the main town square known today as Marafor, and a Capitoline temple facing it. It was believed that the temple was dedicated to God Mars in light of interpreting the Marafor as the Martis forum i.e. the forum of Mars. To the north-west, also in the near vicinity of the former forum, are the remains of the Large Temple dedicated to Neptune, the god of the sea. There are some who interpret the remains as a holy ground surrounding the Capitoline from three sides. The temple, dated to the 1st century, is the biggest in Istria in spite of only a portion of its wall and foundations being preserved.References:
Ängsö Castle was first named as "Engsev" in a royal charter by king Canute I of Sweden (r. 1167-1196), in which he stated that he had inherited the property after his father Eric IX of Sweden. Until 1272, it was owned by the Riseberga Abbey, and then taken over by Gregers Birgersson.
From 1475 until 1710, it was owned by the Sparre family. The current castle was built as a fortress by riksråd Bengt Fadersson Sparre in the 1480s. In 1522, Ängsö Castle was taken after a siege by king Gustav Vasa, since its owner, Fadersson's son Knut Bengtsson, sided with Christian II of Denmark. However, in 1538 it was given by the king to Bengtsson's daughter Hillevi Knutsdotter, who was married to Arvid Trolle.
In 1710, the castle was taken over by Carl Piper and Christina Piper. Ängsö Castle was owned by the Piper family from 1710 until 1971, and is now owned by the Westmanna foundation. The castle building itself was made into a museum in 1959 and was made a listed building in 1965. It is currently opened to visitors during the summers.
The castle is a cubical building in four stores made by stone and bricks. The lower parts is preserved from the middle ages. It was redecorated and expanded in the 1630s. The 4th storey as well as the roof is from the expansion of Carl Hårleman from 1740-41. It gained its current appearance in the 1740s.