The Cross-Island Trek (a.k.a. Te Rua manga, a.k.a. The Needle) is awesome, and I definitely recommend it to any reasonably fit people visiting Rarotonga who want a little adventure. My wife and I completed this hike in about five hours during a short (i.e. 1-night) layover in the Cook Islands on our way to New Zealand. We landed in Rarotonga early in the morning, and by mid-day we were on our way across the island. It definitely makes for a long day, but if you itinerary is similar and you have a day to spend on the Island, this is a great way to spend that day!
We started as recommended on the north side of the island. The start of the trail is easy to find .. just follow instructions in the other TripAdvisor reviews, or look on Google for more information about how to find the trail. I also linked a fairly useful (though not official) website to this review.
The trail is actually pretty easy to follow for the most part. We read some reviews on here that highly recommend going with a guide, but we had no trouble following the trail for the entire length. A few comments on following the trail ...
- The trail is marked with orange triangles. If you hike for a little while and it starts to get rough, and you don't see any orange triangles, go back to the last triangle and see if there's a more developed path. There were a couple of times we ended up on the wrong path, but it was pretty obvious when we hadn't seen a marker.
- There is one stretch near the beginning with no signs. You definitely feel like you're on the path because it's a trail going somewhere, but there are no markers. No worries, keep going as long as the path is developed, and you'll see the markers.
- There is one other area after the summit on the way down where the trail seems to end, and the most obvious way to go is sort of straight down a really steep part that drops off into standing water. Don't go this way .. the trail actually goes up the hill to the left, and the orange markers start up again.
- Definitely go from north to south. If you start in the south, I think you'll have a much harder time following the markers.
A few other general comments ...
- As I mentioned, it took us about 5 hours to complete the trek at a pretty good pace. This is not an easy hike, but it's not too challenging either. We had great weather ... if it's raining, this could be a pretty tricky hike for footing.
- It's worth the short detour to the very top (i.e. to the Needle). Say hi to our friend "Kitten" up there.
- The hike ends at a "waterfall" on the south side of the island. This "waterfall" does not exist year round. Just don't be disappointed if it's not there!
- You can catch the Bus on the south side and take it back to the starting point. It comes once an hour in the clockwise and counter-clockwise directions.
Overall .. definitely recommend. Have fun!