The Halászbástya or Fisherman's Bastion
is a terrace in neo-Gothic and neo-Romanesque style situated on the Buda bank of the Danube,
on the Castle hill in Budapest, around Matthias Church.
It was designed and built between 1895 and 1902 on the plans of Frigyes Schulek.
Between 1947–48, the son of Frigyes Schulek, János Schulek,
conducted the other restoration project after its near destruction during World War II.

From the towers and the terrace a panoramic view exists of Danube,
Margaret Island, Pest to the east and the Gellért Hill.

Its seven towers represent the seven Magyar tribes that settled in the Carpathian Basin in 896.

The Bastion takes its name from the guild of fishermen
that were responsible for defending this stretch of the city walls
in the Middle Ages.
It is a viewing terrace, with many stairs and walking paths.

That is the Parliment Building across the Danube.

Here's an Wikipedia aerial view of the setting: