Twice a year, a hatch in a busy Lisbon street opens to reveal steps leading to one of the Portuguese capital's most ancient sites: a 2,000-year-old Roman structure that still holds the buildings above it together.<br /><br />WATCH MORE: https://thestartv.com/c/news<br />SUBSCRIBE: https://cutt.ly/TheStar<br />LIKE: https://fb.com/TheStarOnline
