For some events acces son foot will be through the front of Guildhall OX14 3HL. The manned entrance at most times of day is on Abbey Close through The Abbey Cinema OX14 3JD. Separate section of this website has more.
Civic parking with a ticket in the car (two hours free with ticket) can be found at OX14 3JD and OX14 3JE. Prices, terms and conditions on White Horse DC website and in the car parks.