I followed a walk down from the top of the Carmelit towards the Wadi. It was fairly easy to follow the signposts and got to the Wadi, which is 3/4 of the way down the hill towards the port. You could get out of the Carmelit at a lower stop if you prefer. The Wadi comprises a bewildering array of roads and alleys with some nice food shops (there appears to be a trail that I couldn't quite work out of 'tastes of the Wadi'. I bought some food to take home and it was delicious. The sights are not particularly spectacular, but it was a super walk down and interesting to see the area.
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