Townson & Crowe (1904) list many an ancient site of Yorkshire in their book, and here on Ilkley Moor we have another site : The Ancient Animal Stone.
It is an Augmented Reality cache, so you need to download the app,and the cartridge.
App For iOS
App for android
The Cartridge. https://mtvrs.io/UtterWorthwhileBluefish
You also will need to have data enabled on your phone. You can get 4G up there. Start the cartridge when you get to the listed co-ordinates, which gives you the information to get to the cache location. The cartridge gives you the information to find the cache, but be warned you will get dirty, and you will be entering a confined space. There are also large drops near here, so watch your footing.
This cache is part of an experiment that allows the use of Augmented Reality (AR) apps to find the cache. At the end of this experiment, Geocaching HQ will decide if this cache will be grandfathered or archived. Geocaching HQ reserves the right to archive this cache at any time if conditions change. If you have found this cache and would like to give feedback on your experience, please fill out this survey.”