Because Colombia has no licensing requirements for guides, those you'll encounter often don't have the experience, talent or English language skills necessary for the job. That goes even for those guides with sterling reviews on TripAdvisor and Tours By Locals—we find that participants often feel guilty leaving an honest review after the one-on-one experience of a guided tour.

An exception is María Isabel Alvarez Ortega, the owner and (for now) sole guide at Discover Cartagena by Locals. An accomplished and insightful story teller, Ortega offers tours that dig deep into to the culture of the city and region. Her Public Market tour goes to the local's only Mercado de Bazurto and includes interactive visits with some of its most garrulous vendors, plus samples of the more unusual specialties (like iguana eggs). Her evening dance experiences—for both salsa and champeta—are co-led by Ortega and an extraordinary dance instructor named Chino. By the end of the evening, even those with feet of lead are up and enjoying themselves. Throughout the tours, Ortega shares frank and fascinating stories of what it was like to grow up in Cartagena, how locals make ends meet, how they party, and how the city has changed. In a town that can sometimes feel like the Colombian Disneyland, Ortega injects a much appreciated dose of reality into the tourist experience.