Harisha/Book 5: Marco Adams is an 8-year old boy. His parents Angela and Michael travel around the world and film documentaries about different cultures, tribes, animals. Their son accompanies them on their travels. Adventures follow him everywhere. Each story happens on a different place of the planet. With Marco, the young readers will travel around the world and see places like India, Kenya, Malaysia, Morocco, Jordan, Myanmar, Peru, and many others. They will meet maharajas, shamans, warriors, archeologists, explorers, different tribes and rare species of the animal world. They will discover the vast amount of magic, hidden in our seemingly well-known world. 'Harisha in the Underground City' is the fifth book of the adventure series about the young traveler Marco Adams ( Harisha ). This time he falls into the depths of the volcanic rocks of Cappadocia, Turkey. The Secret Knowledge continues to lead the child on his exciting journey filled in with new challenges and friends. A special analysis of the ancient map shows the presence of new symbols. Where will they get the little adventurer? Who will help him in the labyrinth of underground city? It looks like the adventure is just about to begin...