To Sua ocean trench in Upolu, Samoa, South Pacific, Pacific

Getty Images/Robert Harding World Imagery

To Sua Ocean Trench

Top choice in 'Upolu

This outrageously photogenic spot is a Samoan icon; skip it to your everlasting regret. Though the first thing you'll see upon entering the grounds is To Le Sua (a smaller, drier depression), it's To Sua that is the star of the show: more akin to a giant sinkhole than a trench, its sheer, green-draped rock walls plummet 20-odd metres to the almost hallucinatory-blue waters of the magnificent pool below. Swimming access is via a precipitous but sturdy wooden ladder; believe us, it's worth the clamber.

When you’ve had your fill of this enchanted waterhole, take the short track to the wave-battered cliffs. The well-groomed garden is a great spot for a picnic.

Gorgeous though it is here, visitors still need to exercise caution: swimming through the underwater passage that feeds the waterhole from the sea is a big no-no, and if you're with kids, beware the child-sized gaps between the ground and the fence that circles the top of the trench.

Lonely Planet's must-see attractions

Nearby 'Upolu attractions

1. Sopo’aga Falls

2.47 MILES

The 54m-high Sopo’aga Falls empty themselves into an enormous gorge close to where the Main South Coast Rd meets Le Mafa Pass Rd. The well-signposted…

2. Uafato Conservation Area

6.37 MILES

The 14 sq km of wild and rugged terrain that comprise the Uafato Conservation Area boast untouched rainforest that marches down from Upolu’s northeastern…

3. Vaiula Beach

6.71 MILES

There's decent surfing to be had at this pretty beach, accessed from Tafatafa village.

4. Lalomanu Crater

8.19 MILES

A short but steep walk (10 to 15 minutes) leads to this extinct crater, blanketed in jungle overgrowth. Home to a huge colony of flying foxes, and with…

5. Togitogiga Waterfalls

10.68 MILES

A glorious spot for a splash, this series of gentle waterfalls are separated by blessedly cool waterholes. It's best to visit in the wet season. To get…

6. Piula Cave Pool

11.58 MILES

Secreted beneath the campus of Piula Methodist Theological College, Piula Cave Pool consists of two blue-green, fish-filled freshwater grottoes, only…

7. Ofa Waterfall

12.71 MILES

This waterfall is reached via an overnight hike into the O Le Pupu-Pu’e National Park.

8. O Le Pupu-Pu’e National Park

13.84 MILES

The name of this 29-sq-km national park means ‘from the coast to the mountaintop’. There are some superb (if rough) hikes to be had here. A trail (six…