I stayed in Cartagena for two weeks and had a great time....that was late eighties. Don't dress flashy as I know of a couple of people who wore gold chains and had them ripped off. I dressed lowkey and kept my purse out of sight. Climbing the hill to La Popa was not a good idea past all the poor, dangling gold and flashing cameras...take a tour bus there.
What was fun was wandering through the old city, sitting at a juice bar with all those exotic fruits freshly squeezed. We asked for bottled water in the mixed drink and not the local stuff put into it and a local ran and got one for us from the store next door to cheers from all the other local customers sipping away, interested to see if we'd enjoy the fruits we'd never heard of before. All the lovely old architecture. I loved the Columbians...so friendly and welcoming. Go through the grocery store in town...I find that a great way to see all the interesting products and what is commonly eaten in every foreign place I go. The music is great in the streets as you walk by stores. We also watched the fresh fish coming in on the boats in the harbour with the backdrop of the old fort used in the movie Romancing the Stone.
When I was there, it was safer on the peninsula where the big hotels were as there were army guards at the gated entrance to this tourist area. Not sure how much it has changed now. A great souvenir was the wonderful jewellry knockoffs of the Incan treasures. I still have a few nice pieces. On the beach opposite our hotel..hmm...sorry can't remember the name of this grand pink stuccoed place, there was a place called El Boney's where we'd eat coconut rice, tomato salad and red snapper, drinking Agua Diente and listening to coffee can music..yum..but I guess the retired boxer from Montreal can't still be running that. Boxing is/was HUGE in Cartagena as a way out of poverty and we chatted to a couple of young boys living on the street and hoping for their big chance at it.
Hope you don't miss it but be wary and enjoy.