Three boatloads of people will be allowed to explore tunnels and crumbling fortificationsEvery nook and cranny teems with history. The tales of war, adventure, death and crime are myriad but for 30 years the people of Plymouth have only been able to gaze across at Drake’s Island – but not set foot there. But on Sunday three boatloads of visitors will make the short hop from the Devon city to explore the crumbling fortifications, the bramble-covered barrack buildings and its mysterious tunnels. The island in Plymouth Sound has been off-limits since 1989 – when an adventure centre on the island...