Somewhere on the Rotorheads forum is a thread about a pilot who was prosecuted for landing on a sports field.
ISTR that he was prosecuted for landing in the carpark NOT the sports field.
Damage to field non if the field is not too wet.
If the field, permission etc is all pukka have fun. Make sure not to attract adverse attention. Not worth the headache.
You may want to check out 'Rule 5' though
You can come closer to objects etc than 500ft for take off and landing as is custom for normal aviation practice.