Sandra's Peaks are a pair of coral peaks that sit offshore from the Sandra's mooring on Saxon Reef. Divers Den describes Sandra's as a beautiful, shallow reef with a wide range of anemonefish, and says that Sandra's Peaks lie offshore, offering depth and a valley between them. For certified divers, the peaks turn what would otherwise be a shallow snorkelling site into a more rewarding dive: the swim out across the sand leads to two coral towers separated by a valley, where the depth increases and the fish life thickens.

The valley between the peaks funnels water, so it tends to hold schools of fusiliers and snapper, and larger fish cruise between the two towers. The peaks are covered in hard and soft corals, and their shaded lower flanks carry sea fans and sponges. Saxon's residents include whitetip reef sharks, which rest on the sand during the day, schools of yellowfin barracuda, anemonefish of several species, turtles, giant trevally and wobbegong sharks under ledges.

Nudibranchs and other small creatures are common on the peaks. After exploring the peaks, divers return towards the boat over the sandy bay and the coral islands of Sandra's itself, which make a relaxing, shallow finish to the dive and a good place for a long safety stop. The site suits Open Water divers comfortable swimming a short distance from the mooring, and gives a good balance of depth and shallow reef on a single tank.

There is also a separate Sandra's site on Norman Reef.

Boat access only. Cairns day boats leave from the Reef Fleet Terminal (1 Spence Street) and the neighbouring Marlin Marina on the city waterfront, with check-in between about 7:00 and 8:00 am; most operators run transfers from city and northern-beaches accommodation, and there is paid parking near the terminal. The run of about 55 km out through Trinity Inlet and across the lagoon to Saxon Reef takes around 75 minutes on a fast catamaran and noticeably longer on slower dive boats or into a south-easterly chop.

Sandra's Peaks are reached from the Sandra's mooring used by Divers Den and other Saxon operators; the peaks lie a short swim offshore from the boat.

The prevailing south-east trade winds (typically 15-25 knots from April to September) are what limit Cairns outer-reef diving: above about 25 knots trips may be cancelled, and exposed eastern moorings are used only in light winds. Summer northerlies are gentler but make north-facing moorings choppy. Box jellyfish and Irukandji are present from about November to May (stinger suits on every dive), and the cyclone season runs November to April, when a system in the Coral Sea can close the reef for days.

Visibility drops after heavy rain and strong winds; spring is usually calmest and clearest. Saxon's western lagoons are sheltered; its weather side is dived only in calm conditions. The peaks lie offshore from the sheltered Sandra's mooring and are more exposed to current than the bay; they are best in light winds and near slack water.

From the Sandra's mooring swim offshore across the sand to the peaks, descend into the valley between them at 15-20 m, circle each peak and return to the bay, finishing among the coral islands in the shallows with a safety stop at 5 m.

Divers Den (Reef Quest, Ocean Quest) – regular from the Sandra's mooring; other Saxon operators occasionally; Saxon is also worked by Divers Den, Reef Experience, Down Under Cruise & Dive, Tusa Reef Tours, Aqua Quest and Reef Encounter; the mooring used on any day is chosen by the skipper according to wind, tide and other boats