Akçakoca is a town on the Black Sea coast to the West of Ereğli that I visited on an afternoon. I somehow did not manage to locate the ruins of a Genoese fortress somewhere in the town. The Genoese paid Constantinople in the 13th century to get some privileges. That is all I know. The town seems to be a popular bathing resort, and seems to be on the expensive side. I did not find it spectacular, with the exception of a modern mosque (the Akçakoca Merkez Camii or Central Mosque) that is amongst the best I saw in Turkey (so far). I took lots of pictures of that, some of the harbour, some of the beach, and returned to Ereğli. I, there were at least three dolphins swimming by, that seems to be a regular occurrence.
Information about the mosque is given on another pbase-site, https://pbase.com/osmantanidik/akcakoca where you can also see some discussion on the merits of the mosque. If you know Turkish see an article in Radikal: http://www.radikal.com.tr/veriler/2004/10/06/haber_130325.php There I read the mimar or architect is Ergün Subası and that its design dates from 1989. It was not opened until 15 years later.