Intermediate 7 minutes
Underwater maps and sketches: drawing a site to understand it
Reading the briefing map and making your own are two different skills
The map a guide draws on the whiteboard before the dive contains, in thirty seconds of strokes, all the information it would take you three dives to discover on your own. Learning to read it, and later to make your own, completely changes your relationship with a dive site.
In this article you'll see what information a dive site map actually contains, how to interpret it, and how to draw your own sketch by combining bearings, distances, and landmarks.
Your own sketch turns an unfamiliar site into known ground, and it's the basis for any navigation that goes beyond a simple out-and-back.
Reading the briefing map
A dive site map isn't a scale drawing: it's a functional diagram. What matters isn't that the distances are exact, but that the relationships between elements are.
The information it usually contains is always the same. The entry point and the exit point, which don't always coincide. The general orientation: where the shore is, where the open ocean is, often with a north arrow. The depth profile, showing where it's shallow and where the bottom drops away. The notable features: the well-known formation, the wreck, the cleaning station, the spot where a particular species tends to show up. And very often, the expected current direction.
While listening to the briefing, it helps to mentally translate that drawing into what you're going to see: if the guide says the wall will be on your right as you descend, picture yourself already swimming with the wall on your right. That advance translation makes the site feel recognizable from the very first minute.
And there's a question almost no one asks that's worth asking: which way out if you need to leave early. At many sites, the answer isn't obvious from below.
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