Of the 2 parts of this WHS I enjoyed the ruins of Panama Viejo more than the neighbourhood of Casco Viejo. We easily covered both sites in a day. The ruins are well preserved in a state of (mostly) unrestored rubble but it is not hard to get a feel for the layout of the settlement and there is a very good museum on site to help get the most out of it. As the original settlement of Panama and the first by the Spaniards on the Pacific coast, a visit here was essential to our overall appreciation and understanding of the colonization of the new world, a theme we'd been following quite closely for the last couple years in our travels. 

Casco Viejo is just another small colonial core much like any other in Latin America and unique only in its later French influences. Restoration work is still ongoing but there are still many empty buildings shells between restored sections. This adds a degree of character to the area and I wonder if this is in part by design. I'd like to see the overall plan to see what the final goal for the restoration work is. If they even know! If anything the tourist dollar should keep them motivated to keep working at it. There is still a very visible police presence in the area but all the uber drivers I asked confidently replied that security concerns were a thing of the past, just don't go wandering out of the tourist zone.