The event includes kayak, trekking and mountain biking for teams of four.

It is considered the ultimate test of physical and mental limits, a spokesperson for the organising group said.

"There is no question, the race is tough and it is real adventure," the spokesperson said.

"Your body will be totally exhausted, your brain will be begging you to stop and you'll have had little or no sleep for 48 hours.

"Then if you are one of the lucky teams, you will crawl across the finish line. This is certainly not your average weekend."

With about 250 competitors already entered in teams of four, just finishing the endurance epic is considered a win.

"There is certainly a sense of elation and achievement like nothing else when teams cross that finishing line.

"They will have taken their body and mind past anywhere it has been before. They will have shared incomparable experiences with their team mates and learnt about themselves. Ultimately they will have found that their limits are just an illusion."

The Mountain Designs GeoQuest features three categories - Premier or mixed teams, all-female or all-male.

To add extra pressure to the teams, the team of four must not be separated by more than 100 metres throughout the race. Each team is allowed a support crew.

The non-stop 48 hour adventure race features the full course and the Geo-Half.

The full course is the ultimate test for a team while the Geo-Half is approx half the distance but still allowing the full 48 hours. The Geo-Half is ideal for those who want to give adventure racing a try, but not commit to the full course. It is an event with an emphasis on teamwork, fitness and adventure.

Port Macquarie last hosted the GeoQuest event in 2010.