=> "Please present the places you have visited so far."
I think my translation should be correct and it wasn't much trouble to come up with it. However, I'm not really sure why there is
Usually I would expect the construction た-form + ことが + ありました like 私は中国に住んだことがありました。
So what seems unusual to is the use of の instead of が and the use of present tense ある instead of past tense ありました.
Since the verbal complex "verb + ことのある" modifies the noun 観光地 I could imagine の acting in the same function as here:
子供の描いた絵です。 vs. 子供が書いた絵です。
I'm just a bit cautious with this analogy since in these 2 examples above, the modified noun is the subject. I only rarely encountered this use of の in my textbook so far and I can't remember a situation where this was done with the object of a sentence (as it is the case in the sentence in question), so I don't know if this interchangeability of の/が applies here too.
Concerning ある instead of ありました, well, I'm a bit clueless right now.^^ It's the main reason though that I suspect that ことのある might not be a variation of the た + ことが + ありました pattern but instead something else.^^