Our hotel, the Best Western at Kinsky Garden, is across the street from Petrin Park, easily my favorite place in the city, and the first place we investigated in our trip. I’ve taken several walks there, though they might properly be described as hikes; all of the paths zig-zag up a steep hill (roughly 1000 feet of change in elevation), and I’ve frequently been grateful for the stone paths, which help a bit with traction. 
The elevation change gets us some of the best views of the city, particularly St. Vitus Cathedral and the castle.
Sydney is framed by one of the gates through the Hunger Wall, which snakes down the side of Petrin Park. The Hunger Wall dates from the 14th century, though I would guess the graffiti is more recent.
Erin
Alan Schmierer