Most day trips from Cartagena are sold to you before you've worked out what they are. Here is how we'd sort them, from where we sit on Bahía de Cholón, on Barú.
There are really two kinds. Water days, where the point is the sea and you give up most of the day to a boat. And road days, where the point is a place inland and you give up most of the day to a vehicle. Mixing the two in one day is how people end up seeing neither properly.
The one water day we'd defend: Corales del Rosario National Park
Corales del Rosario is the day trip to protect, because it's the only one where the thing you came for is genuinely there. It's a protected national marine park of coral reef and islands off the Barú and Rosario coast, and the living reef sits offshore, around the islands, not along the mainland sand. That distinction matters more than anything else on this page. Plenty of people buy a "snorkelling day" and are set down on a crowded beach with nothing under them but sand and silt, then conclude Colombia's reef is a disappointment.
Give it the whole day, and treat the boat time as part of it rather than an obstacle. We've written the longer version of this, including what the park actually protects and how it looks from our side of the island, in our piece on Corales del Rosario.
San Basilio de Palenque, if you want a road day with weight to it
Palenque is the most substantial inland day near Cartagena, and it isn't close. It sits about 50 km from the city, roughly an hour and a half by road, in the department of Bolívar.
What it is: the town founded by Benkos Bioho by Africans who escaped slavery in Cartagena, held as free territory, and recognised as the first free African town in the Americas. UNESCO lists its cultural space as a Masterpiece of the Oral and Intangible Heritage of Humanity, which covers the language, the drumming and the funeral rites rather than any single building. The centre of it is Benkos Bioho Square.
Our honest view: this is a day for people who want to listen rather than photograph, and it's a poor fit for a quick stop squeezed between other things. It's also the one trip on this list we'd tell you to do from the city rather than from us. Three hours of road, round trip, plus our boat each way, is not a day anyone enjoys. If Palenque matters to you, build it around a night in Cartagena.
The National Aviary of Colombia, which is already on our island
The aviary is on Barú, the same island we're on, which makes it the rare attraction here that doesn't need a crossing back to the mainland. It's a large walk-through collection of Colombian birds laid out across open aviaries.
Go as early in the day as you can. The walk is long, much of it is in the open, and the middle of the day on Barú is the worst part of the day for walking anywhere. We've set out what to expect and when to go in our guide to the aviary.
Playa Blanca, with our reservations stated plainly
Playa Blanca is Barú's busiest beach, and it's the single most oversold day trip out of Cartagena. The sand and the colour of the water are real. So are the crowds, the vendors and the volume of boats arriving at once.
We won't tell you not to go, but we'd tell you to go early and not to make a whole day of it, and we'd tell you it is not where you'll see reef. Our read on Playa Blanca goes into the detail, including who it actually suits.
Bocachica, which is a visit rather than an attraction
Bocachica is a village, and we'd ask you to treat it as one. In our own words to guests: it's a village with no running water and no paved roads, but so much soul you won't believe it. Do not expect chic restaurants and bars. This is island life as it's actually lived.
It's the least packaged thing on this list and the one that asks the most of a visitor. Go with that understood, and it's the day people tend to remember.
Cartagena's walled city, which most people treat as a day trip in reverse
If you're staying out on the islands, the walled city becomes your day trip rather than your base. It works best in the late afternoon and evening, when the stone has stopped holding the heat and the squares fill up.
We've written both halves of that day: a walking tour timed around the heat, and where we send guests to eat when they've made the crossing.
How the geography changes what's worth doing
From Cartagena, everything on this list is an excursion. From us, on Bahía de Cholón, the island things are close and the mainland things are far, which inverts the usual advice.
Our boat runs between Cartagena and Casas Altas in 30 minutes to an hour. Door to door from Rafael Núñez International Airport to us is an hour. That's the number to plan around: anything that adds three hours of road on top of two boat crossings is a day spent travelling, not a day out.
The pattern that works: keep the water days for the island side, and save the road days for whichever nights you spend in the city.
What we'd leave off
We'd skip anything advertised as three or four destinations in a single day. Cartagena's day-trip market rewards volume, and a boat that calls at a beach, a lunch spot and a snorkel stop before three in the afternoon has not given you a day at any of them.
One place, properly, beats four seen from a boat ramp. That's the whole of our advice.