- en.wikipedia.org OpoleIn 1521 the Duchy of Opole inherited the Duchy of Racibórz (Ratibor), by then also known by its German equivalent – Oppeln. The second castle of Opole was...
- fr.aroundus.com p/12353000-opole-castleOpole Castle, Château en Pologne. Le château d'Opole, également connu sous le nom de château des Piasts, se trouve dans la ville d'Opole.
- upper-silesia.tourpoland.net opole/defensive-…Address: ul. Piastowska 14 , 45-082 Opole. Castle tower in Opole. Info. Upcoming events. Comments (0).
- commons.wikimedia.org wiki/Category:Opole_CastlePiast Tower (Opole) (3 C, 47 F). Media in category "Opole Castle". The following 14 files are in this category, out of 14 total.
- staypoland.com castles-and-palaces-of-the-opole-…Today, after a complex renovation, visitors can attend a multimedia exhibition about Opole’s history, the Piast Castle, and the tower itself.
- tropter.com en/poland/opole/tower-of-the-upper-…Tower of the Upper Castle is the only remnant of one of the Opole castles. ... History of the Upper Castle in Opole is hidden in the darkness of history.
- medievalheritage.eu en/main-page/heritage/poland/…Opole – castle on the Ostrówek. reconstruction of the castle in the late Middle Ages, photo source Wikimedia Commons.
- en.wikivoyage.org wiki/OpoleAs the former Duchy of Opole started changing hands between surrounding kingdoms and empires, the castle was subjects to periods of ruin and reconstruction.
- http://polishcastles.eu castles/opole/opole.phpHistorical outline: Former name: Oppeln. In the past two castles existed in Opole: one was situated on Ostrówek island, and the second on so-called Górka.
- http://en.szarawilla.pl polecamy-w-opolu-i-okolicach/History of Opole, Castle in Ostrówek, crafts, literature and the post-war Opole are just some of attractions.