The Halászbástya (Hungarian pronunciation: [ˈhɒlaːzbaːʃcɒ]) or Fisherman's Bastion is one of the best known historical monuments in Budapest, located near the Buda Castle, in the Várkerület (Buda Castle District). Since 1987, it has been designated a UNESCO World Heritage Site as part of the Várkerület District (Buda Castle District).

It offers a unique panorama of Budapest from its Neo-Romanesque lookout terraces. The Fisherman's Bastion's main façade, parallel to the Danube, is approximately 140 metres long, of which the southern aisle is about 40 metres long, the north is 65 metres long, and the ornate central parapet is 35 metres long. Its seven high-pitched stone towers symbolise the seven chieftains of the Hungarians who founded Hungary in 895.

The original walls were built in the 1700s, forming part of the walls of a castle. A consensus among historians is that in the Middle Ages this part of the castle wall was protected by the guild of fishermen (halász), who lived under the walls in the so-called Fishtown or Watertown. The current structure was built between 1895 and 1902, in Neo-Romanesque style, on the base of a stretch of the Buda Castle walls, by architect Frigyes Schulek, who was also responsible for the restoration.