This cache replaced a puzzle cache. This short stretch of former railway is part of NCR27.
This track leads to Wilminstone Viaduct which used to be the line to Okehampton.
The missing link refers to the railway line west of the cache which for some reason has not been converted to a cycleway, (cyclists have to use Old Exeter Road which involves a very steep hill) the missing link is between this cache and Around Tavistock 4.