Fort of Ameixoeira - Credit: Wikimedia Commons
The Fort of Ameixoeira, also known as the King Carlos I Fort, is located in the former parish of Ameixoeira, now part of the Santa Clara parish of Lisbon, capital of Portugal. It currently serves as the headquarters of the Serviço de Informações de Segurança (SIS), the Portuguese Security and Intelligence Service. It was constructed as part of the Campo Entrincheirado (Entrenched Field), a group of fortifications built at the end of the 19th century and beginning of the 20th century to protect Lisbon against possible invasion. Read more on Wikipedia
Source: en.wikipedia.org