Many people were attracted to Edinburgh to seek their fortune, but once within the city walls they found out there was no employment. They could not leave freely as there was a charge to leave the city and with no employment, people could not afford this fee. The city officials' method to deal with homelessness was to make it illegal. This drove the homeless into hiding and, as the city developed, they were quite literally underground, which leads to the first location. Many people have heard of the Underground Vaults, they are regularly visited and so they are probably the best known location included in this book. I decided to include them, as although people may have heard of them, they may not know much about them or what to expect when visiting.