It is a 10 minute walk from the ferry terminal to this historic entrance to the Barrio Historico and great way to begin your visit. You can climb up on the wall once you have gone through the gate to have a nice view over a cannon to the River Platte. I agree that waiting to choose the optimal time for your "photo op" of the gate is a good idea. I was able to take a picture sans tourists but I really liked the one with the schoolchildren on the drawbridge.
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