Colombia has been at war with itself for a generation, and violence has been the country's single biggest killer. Plagued by guerrilla conflict, kidnapping and drug cartels worth billions of pounds, on an average day in Colombia someone is murdered every 30 minutes and four people are kidnapped. With a population of 45 million, Colombia is one of the largest countries in Latin America. Bang in the middle sits the infamous capital, Bogota, home to seven million people.