Archaeologists working in Umm Al Quwain believe they may have located the ancient lost city of Tu'am. It is thought the city was once the capital of a territory, on the Gulf coast of what is now the Emirates, and a pearl fishing centre famed for the quality of its gems. So renowned was Tu'am at its peak around the sixth century that it was written of in ancient Arabic texts. Here, host Sarah Forster speaks to The National's John Dennehy to hear why experts believe this is the fabled city of Tu'am, and why it was eventually lost to the ages.