Meet the site
Perpendicular Wall is Christmas Island's most celebrated boat dive, and Extra Divers rate it one of Australia's most dramatic wall dives: a vertical cliff at the north-western tip of the island that falls away into the abyss. The name is literal – the face drops almost vertically from about 5 m, and the island's volcanic flanks continue down for thousands of metres.
Descriptions from Diveplanit, Divernet and Scuba Diver Life agree on the character. The dive often starts at an overhang or shallow cave with red sea fans, then continues along the wall, where corals and gorgonians lean outward to catch light and current. Sea fans, feather stars and hydrocorals make the face a riot of colour. The fish life moves in two directions: hundreds of black triggerfish and pyramid butterflyfish and schools of fusiliers streaming up and down the face, reef fish moving along it, and blue-lined angelfish among the invertebrates. Sand cascading down from above settles like snow on the coral. At around 32 m a school of batfish is often seen off the wall.
Out in the blue, this is Christmas Island's big-animal site. Extra Divers list sharks, sailfish and whale sharks; Divernet mentions a strong possibility of manta rays and whale sharks; and dolphins are frequently seen from the boat before the dive. The return is along a shallow reef at about 5 m, ideal for a long safety stop.
The site is advanced because of the combination of a bottomless wall and currents that can be strong, and because the long boat run means it is only possible in calm conditions. It suits experienced divers with good buoyancy and depth discipline. Those who dive it tend to agree with the Diveplanit author's advice: slow down, because there is plenty to see.
Research this site before booking Stored site notes may be historical. These questions highlight gaps without turning old instructions into a current dive plan.
Perpendicular Wall is recorded as Wall in Christmas Island. The listed access is boat. Confirm the actual meeting point, route and permission to visit; a map pin does not establish any of these.
Topics flagged by the stored research
These are questions prompted by the existing notes, not a verified or complete hazard assessment.
- Current and timing
- Ask how the operator assesses the current window for the actual route. Historical tide notes are not a departure instruction.
- Other water users
- Ask about vessel activity, exclusion areas and the agreed surface arrangements.
- Planned depth
- Confirm the intended route and training requirements; the recorded maximum is not a target.
Historical access notes exist for this record, but have not been independently verified for current use. Request current directions from the operator or site manager rather than following an old entry description.
Questions, answered
Is Perpendicular Wall suitable for my certification?
The record lists Deep/Advanced + experience. That does not establish suitability for every route or day. Share your training, recent experience and equipment needs with the operator and ask about the specific proposed dive.
Can I book Perpendicular Wall through YouDive?
YouDive is an independent research directory. Contact an operator directly to confirm whether it currently runs the trip, the inclusions and the booking terms.
What you might see
Sea fans, gorgonians, feather stars, hydrocorals, black triggerfish, pyramid butterflyfish, fusiliers, blue-lined angelfish, batfish, grey reef sharks, silvertip and whitetip sharks, sailfish, manta rays, whale sharks (Nov–Apr), spinner dolphins
Location
Near-vertical wall at the north-western tip of the island, dropping from 5 m into the abyss; the island's most famous boat dive.
Facilities nearby
Departs Flying Fish Cove jetty/ramp.
Before you make plans
Conditions, access and operator schedules can change. This is a location guide, not a dive plan. Ask a local operator about current conditions and suitability for your training and experience.
Sources & further reading
diveplanit.comextradivers.com.audiveplanit.comdivernet.comscubadiverlife.comxray-mag.comextradivers.com.auchristmas.net.auchristmasislandstories.org.auRecord updated 27 Sept 2026. Source claims are being reviewed.