Delhi is much more than just the capital of India. It is a city with an amazing history. So many times, it has been the major city or capital of India, from the earliest Mahabharata days to the Rajputs to the Delhi Sultanate to the Mughals to the British. Each time the new rulers left their mark on the city. As a result, now we have a Delhi which has the mark of at least seven or eight different historical cities, if not more. In this book, we review the different historical cities of Delhi. We use the Delhi metro, which is currently probably the best developed metro in India, as the preferred means of transport to see the sights of the seven cities of Delhi. We hope that this short guide will help the reader the experience a little bit of what Delhi is all about, its people and its history. In this book, we do not cover all the historical sites or attractions of Delhi, such as the many modern museums, markets and other attractions. Rather, we focus on the sites that form part of the historical cities of Delhi and those that are located within the historical boundaries of those cities. This book was born out of many travels and exploratory walks made by the authors in Delhi, where they live.