Anywhere more than a mile from a town or maybe 5 miles from a big city should be fine, to be honest. There are special
dark sky reserves dotted around the place, and national parks would be good too. Ideally somewhere fairly south so the sun sets earlier... but you can only really manage an hour or two of meteor watching at a time, anyway. Bring hot drinks and wrap up warmer than you think you'll need to!
Mr D's Mum lives in the middle of one of them. If you're lucky, the stars are amazing after midnight when all the street lights are off and nobody's left their security lights on because it's pitch black and perfect for burglars/a guaranteed way to end up head first in a river or leat. Trouble is, to get away from the village, you need a car or you're likely to come a cropper courtesy of
a) blanket bogs
b) ditches
c) pissed up Cornishmen on the way home from a pub
d) rapidly changing and actually incredibly dangerous weather - hypothermia in the middle of a heatwave isn't unusual
e) the Hairy Hands
f) the Evil Rider
g) Vixana the Witch
h) Adders
i) Unexploded Ordinance
j) cattle
k) ponies
l) ticks
m) poachers/lampers/nutters
n) valley mires
o) combines travelling to the next farm during harvest
p) featherbed bogs
q) flash floods/river rising
s) military movements
t) rabbit holes
u) tors
v) quarries
w) the stables (where something has died in a mire and fertilised the surrounding area)
x) a farmer with a gun and no more patience with uncontrollable dogs
y) local lads pissed off with twats camping and shitting over their Dad's land
z) getting lost because it's fucking isolated, the mobile signal is
variable, there's no chance of calling it quits and getting a cab back to civilisation
The last thing that Moorland Rescue needs is their time taken up with wailing twats and their mutts because they wanted a jolly experience and ended up with a Hound of the Baskervilles style debacle instead.