Just an hour's boat trip away from Cartagena lie the magnificent Rosario Islands, which belong to Colombia's only underwater natural park (the Rosario and San Bernardo Corals National Natural Park). Abundant marine wildlife (including over 50 species of corals) and some of Colombia's best beaches draw in many in search of relaxation and active pursuits such as snorkelling and diving. Isla Grande is best for kayaking through unique mangrove forests and seeing the phosphorescent plankton light up the waters of a brackish lake at night, while Playa Blanca is Cartagena's most spectacular white-sand beach (also reachable by land). It should be said that the company you choose to tour with has the potential to make or break the experience. Low cost tours can mean multiple intermediate stops en route to your destination, as well as unpleasant surprises such as no transfer back to your hotel. Try and choose a trusted company with consistently good reviews, or opt for a private tour. Mind that seas may be rough at certain times of the year, particularly in December and January, when tours on smaller boats may even become dangerous.

Check out the City Opera House's Calendar for a myriad of performances and events. This historic downtown theater hosts comedians, musicians and theatrical performances, as well as cultural and educational events.

This 1-mile hike at Kaiwi State Scenic Shoreline Park takes visitors over beautiful hills to the historic Makapuʻu lighthouse, and it always provides places for having a break and for admiring the breathtaking scenery. During the winter months, it is possible to view humpback whales during their long migrations.

Located on the shoreline of Lake Michigan, one of the U.S.'s five great lakes, Sleeping Bear Dunes is a natural wonder that has been marked for preservation for its awe-inspiring beauty and natural resources. It takes its name from a Native American legend concerning its formation. It consists of Sleeping Bear, Empire and Pyramid Point bluffs that overlook the lake, and Manitou Islands, which are located about 15 miles offshore. There are numerous activities available to visitors of the park that include camping, hiking, kayaking and canoeing, biking, skiing, fishing, or simply exploring the myriad of ecosystems that are home to a diversity of plants and wildlife.