The Spring Challenge is an adventure race for women which began in New Zealand in 2007. It is a team event where 3-women do the entire course together, traveling through the stages as a unit - meaning - it is not a relay team where different team mates do different stages, in adventure racing, the whole team does everything.
Because navigation is a factor, each year the event has a brand new course in a different location, so even for the regular participants, it's always refreshed and exciting, plus there's not a big advantage over teams who are new comers to the sport.
The first step of doing an adventure race is having an appetite for adventure and a desire to embark on a challenge. There are 3-main options for the event, 3, 6 and 9-hour options, plus categories within. Decide what suits your ability and taste best, then build a team of 3-women with a shared goal and ideally, similar ability.
Check the gear list and make sure you have or can source to equipment required for the event. You also need a support crew, 1-2 people who can drive a vehicle around the course area meeting you at various points to resupply and change equipment - but this depends on the course design and location, some years the event is 'self-supported', where you don't require a support crew.