E: 29/02 Win a 988GB High-Speed Waterproof USB Memory Stick

One-Eye

Harbour Guides

Where is the alternating photo?

My Answer = B. Povoa de Varzim

I can't find a close match for the photo, but noting the height of the pilings on the floating jetties, there must be a big tidal range, and Povoa de Varzim is in Portugal on the Atlantic. The other two are in the Mediterranean.

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AR2012

I mainly saw the White Caps for lightening strikes in images of Povoa de Varzim in google. 

Scorpioangel

I agree with One-Eye, having looked at various pictures of the marinas, Povoa is the only one with those pilings