Fuerte San Lorenzo is the landmark at the very entrance of the Rio Chagres. We did not have the opportunity to visit it but the following web site has more pictures of the fort http://www.galenfrysinger.com/panama_fort_san_lorenzo.htm. 

We motored for at least one hour admiring the tropical forest and looing for the best anchoring spot from where we could do some explorations. We read in our cruising guide that there were paths in the forests and that it was also possible to sail up the Lake Gatun damm.

Our first incursion in the dense vegetation of the forest was somewhat magical: trees were very high forming a green dome overhead, with many butterflies fluttering around us when Heiner spotted the large blue morpho!