In diagram it looks like this.
From the river it appears like this.
There are several ways to get there. You can cross the famous Chain Bridge (below)
and walk up. This is only for the supremely fit or the supremely stupid as the photo below shows.
Alternatively you can cross the Chain Bridge and and take the cute little funicular up to the top.
I like this one as it makes sure you appreciate its age by artfully leaving the older stonework exposed.
Even the mailboxes are cool.
A few short blocks more and you are in the crowded square that houses the magnificent Matthias Church.
with its colorful patterned roof decorations
No matter the history, today it is the view from the ramparts that draws the visitors. You have gob smacking views up and down the Danube from Margaret Island to the Gellert Hill. The panorama below starts at the Parliament complex and sweeps downstream until you can just see the Liberation Monument on Gellert Hill.