Penang Hill or Bukit Bendera (in Malay). This is not only a natural, but also historical sightseeing: in XVIII rich British organized horse rides here, and wealthy colonialists built houses.
Now the Hill is cut of paths and there is a funicular to the top of it.
But climbing on foot is much more attractive then to go bu funicular.
On the top of the hill, in addition to a delightful panorama, a cafe, a temple, you can always watch cute and good-natured (unlike macaques) monkeys - spectacle thin-bodies.
One of Bukit Bendera's slogans reads: "If you haven't visited Penang Hill, then you've never been to Penang Island."