Cafe del Mar has a great location, on top of the wall, with (depending on your luck) a view of the sunset. I wasn't expecting to enjoy Cafe del Mar, but found it so comfortable, that I came back the following evening.
Most of the complaints are valid. It's touristy and the drinks are overpriced (for Colombia). That being said, you're on vacation so just enjoy yourself. Sit down, nurse a single drink, and chat with your partner/friends.
Other reviewers say you can just bring a beer and sit nearby. That's definitely true, but you may be bothered by touts who hang out in that area.
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