Hero Underground Xtreme Experience at the Deepest Slate Mine in the World for Two | Scaling | Virgin Experience Days / Voucher Gift Virgin Experience Days For Couples/Him/Her/Mum/Dad/Boyfriend/Girlfriend/Wife/Husband/Partner/Family Things To Do | Push Yourselves to the Limit With This Hero Underground Xtreme Experience at the Deepest Slate Mine in the World for Two. Great for Those Wanting to Push Themselves That bit Further, the Experience Lasts Approximately six Hours, Including Kitting up and Travelling to the Mine. A Head for Heights is Vital as You’ll be Climbing via Ferrata Ladders, Traversing and Abseiling on a Large Scale. You’ll Ascend Down a Zipline That’ll Take you to the Lowest Accessible Point in the UK, 1,300ft Under Solid Rock. With Narrow Ledges and old Decaying Bridges, This Challenge is Sure to Leave you Buzzing Long After It’s Over. | Wales - Gwynedd