@GlomOfNit it’s in the tier 4 rules on gov.uk in the travel section:
Travel
Travelling within a Tier 4 area
If you live in a Tier 4 area, you must not leave your home unless you have a reasonable excuse (for example, for work or education purposes). If you need to travel you should stay local – meaning avoiding travelling outside of your village, town or the part of a city where you live – and look to reduce the number of journeys you make overall. The list of reasons you can leave your home and area include, but are not limited to: blah blah blah
I wouldn’t worry about it though. In the same tier 4 guidance it says you can travel to all sorts of leisure places - it’s in the Meeting Others Safely section of tier 4:
You can exercise or visit a public outdoor place:
by yourself
with the people you live with
with your support bubble
or, when on your own, with 1 person from another household
Children under 5, and up to 2 carers for a person with a disability who needs continuous care are not counted towards the outdoors gatherings limit.
Public outdoor places include:
parks, beaches, countryside accessible to the public, forests
public gardens (whether or not you pay to enter them)
allotments
the grounds of a heritage site
outdoor sports courts and facilities
playgrounds
My conclusion is stay local-ish, but I really wouldn’t get excited about someone driving a shortish distance to go somewhere different.