Make sure you have some euros in cash, because you'll have to pay to visit this castle and they don't accept credit cards - you'll have to go down the hill for ATM :)
Historic building in very good condition and well worth a visit. Great facilities including a lovely cafe and lavatories. Parking nearby is difficult, use R. do Castolo parking, short walk away.
Great views from the castle walls across Silves and the hills surrounding it. Reasonable price at €2.78 for adult entry. Less for children, students and over 65s
O Castelo é uma das mais notáveis obras de arquitetura militar árabe, com mais de mil anos de existência. + info: http://www.cm-silves.pt/pt/menu/106/castelo-de-silves.aspx
