Australia — East Coast, Cape Sidmouth to Cape Grenville & the Barrier Reefs (1843–48)

Australia — East Coast, Cape Sidmouth to Cape Grenville & the Barrier Reefs (1843–48)

The Admiralty chart that unlocked Australia’s far-northern reef frontier

At the very top of Queensland, where the Great Barrier Reef fragments into countless shoals, channels and coral walls, the sea was once almost impassable. Between Cape Sidmouth and Cape Grenville, ships faced one of the most dangerous stretches of water in the southern hemisphere.

This remarkable British Admiralty chart, surveyed between 1843 and 1848 by the crews of HMS Fly and HMS Rattlesnake under Captain Francis Price Blackwood and Captain Owen Stanley, records the moment this lethal reef zone was finally measured, charted and made navigable.

Engraved by J. & C. Walker, it became the working map that allowed vessels to push north toward Torres Strait and the great trade routes of the Pacific.

This is not a decorative map.
It is the blueprint of Australia’s northern sea gateway.

⚓ What This Chart Shows

This finely detailed Admiralty sheet lays out one of the most complex marine environments on Earth.

• The northeast Queensland coastline from Cape Sidmouth to Cape Grenville

• The outer and inner Great Barrier Reef system

• Detached reefs, coral heads and shoals

• Hundreds of bathymetric soundings showing safe depths and danger zones

• Coastal relief shown by hachures and spot heights

• Greenwich prime meridian — true Admiralty navigation standard

This was the chart captains depended on to survive the reef maze approaching Torres Strait.

🧭 Why This Chart Works

Most reef maps show where coral lies.
This shows where ships could pass.

• Surveyed by HMS Fly and HMS Rattlesnake — legendary hydrographic vessels

• Compiled from years of perilous reef exploration

• True British Admiralty production — the gold standard of navigation

• Dense technical detail — soundings, shoals and safe channels

• Museum-grade engraving by J. & C. Walker

This is the chart that turned Australia’s northern coast from a barrier into a maritime corridor.

✨ Premium Finishes

Every Cape Sidmouth to Cape Grenville (1843–48) Admiralty Chart is printed in Australia using archival methods to preserve every fine engraved line and depth figure.

📐 Size

754 mm (W) × 1000 mm (H)
A tall portrait-format wall map that emphasises the dramatic reef-lined coastline and the dangerous approach to Torres Strait.

🎯 Ideal For

• Maritime and naval history collectors

• Yacht clubs and sailing institutions

• Museums and libraries

• Reef researchers and environmental centres

• Anyone fascinated by Australia’s northern frontier

🤝 Our Commitment

• Printed in Australia with professional colour management

• Archival pigment inks for long-term stability

• Premium laminates and canvas for durability

• Natural timber hang rails for elegant presentation

• Hand-checked and carefully packed before dispatch

Before Torres Strait could be reached, this reef barrier had to be conquered.
Choose your finish and bring the chart that made it possible onto your wall.