Nav. course
Home Nav. course Sailing Greece Turkish Coasts Yacht charter Gulets                          

This is an advanced online course on marine navigation, providing you with the “conditio sine qua non” of offshore sailing. Nowadays most sailors tend to rely on modern equipment like differential GPS or Radar to navigate them through hazardous waters. Not only is such reliance unwanted and possibly dangerous, also the act of navigating by yourself is actually a lot of fun, especially when sailing in Greece or Turkey, which are the perfect cruising areas to learn how to sail.

What is navigation?

Navigare necesse est, vivere non est necesse” is latin for: to sail is vital, to live is not. This phrase tells us that both sailing and the “conditio” of positioning are highly intertwined. Indeed, the art of navigation enables you to set a course and sail to your destination by using only nautical charts, a compass and your common sense.

The aim of this course is to teach you how to navigate safely while using the minimum of resources: methods that have been in use since the Middle Ages, and are still applied by the professionals. This course greatly extends on - for instance - the ASA and RYA courses and gives you the insight and feel of a seasoned navigator.


This is chapter 0: Use the moving anchor logo on the right of this page to navigate through the course.
Alternatively, click on the links below to study the chapters or download the complete navigation course as well as exercises and answers as PDF PDF download

Chapter 1 - Positions    
Chapter 2 - Nautical chart    
Chapter 3 - Compass    
Chapter 4 - Plotting    
Chapter 5 - Piloting    
Chapter 6 - Tides    
Chapter 7 - Tide prediction    
Chapter 8 - Currents    
Chapter 9 - Navigation aids    
Chapter 10 - Lights and Shapes    

Math - Running fixes    
Math - Distance of horizon    
Math - Vertical sextant angles    

Compass deviation table    
Lunation: phases of the moon    

Anchors, anchoring and
Mediterranean mooring techniques    

Flags and etiquette    

Style guide: notation of distances
and coordinates used on this website    

Celestial navigation course — zipped PDF


Clouds: fair weather cumulus versus cumulonimbus - how to forecast showers.
Raindrops aren't spherical.
The wind chill forecast.
How to forecast the Meltemi wind.
Beaufort wind scale.
Learn to sail: recognized sailing schools and yacht charters in Greece


This course deals with the key cognitive issues associated with the art and science of navigation and communicates them with well crafted prose and exceptional clear graphics.
I found this online material quite valid for our local US sailors & instructors and I strongly recommend it as a splendid teaching tool.
Ralph Naranjo
Safety at Sea Committee Chairman US Sailing

"Wonderful" material, I run a school in Canada and have never come across materials on the net like this. Do you have a book or can we purchase a disk for training purposes? Regards,

Glenn Lethbridge
CYA Instructor Evaluator

Hi. A great site, your nav course is very well developed. I am an instructor of the Australian Volunteer Coast Guard.
What you have done is really good and I wait with baited breath to see how far you can take this.

Chris Salmon
Australian Volunteer Coast Guard

Truly fantastic site. This navigation tutorial was stimulating. I want to throw my GPS overboard.

Bob Church

Excellent course. I can tell that you have taken a lot of time to develop this.
I know - I am responsible for the navigation course that is used by the USCG Auxiliary.

Derrick Young
US Coast Guard Auxiliary


Books·charts Sitemap| A-Z Contact RSS| Charterguide PDFs
20 Sept 2016
    © 2000 – 2016 Diederik Willemsen | E-mail me
Site map | A-Z index | Register

 RSS XML Feed | | Level AA conformance icon, W3C-WAI Web Content Accessibility Guidelines 1.0 | |