People were given the right to walk across open country - mountain, moor, heath, down and registered common land - by the Countryside and Rights of Way Act 2000.
However, this is not a right to roam anywhere. You can walk on mapped open access land but must keep 20 metres from houses and you are not allowed in active quarries or on railway lines and landing strips. You must also obey any restrictions.
You can see maps of access land and current restrictions on Natural England's website.
York Ramblers have worked with the public rights of way team to produce a booklet of challenging walks on open access land. You can view information about walks on open access land on the York Ramblers website.