The Afterwork Navigation League event Wellington called "The Wild West" explores the rural areas west of Wellington, and is one of a series of 3 hour rogaines in the evenings. These were initially designed as practice for longer events, but are perfectly good as ends in themselves.
These events are usually 3 hours, but occasionally might be shorter. Maps are available from 5:20pm, briefing 5:50pm, and rogaine from 6pm to 9pm. For locations further out these might be half an hour later. If you can't get there by then why worry - just rogaine for a shorter time. In fact if you want a shorter period tell the organiser and just do it!
3 hour off road rogaine