Shom L Nautical Chart – Mediterranean Sea, Black Sea and Sea of Marmara

Introduction

The Shom L nautical chart for the Mediterranean Sea, Black Sea and Sea of Marmara is a folded paper nautical chart designed for route planning and navigation in the Mediterranean and in the maritime areas covered by Shom hydrographic charting. Published by the French Hydrographic and Oceanographic Service, Shom nautical charts are official nautical documentation used by leisure sailors, offshore navigators, maritime professionals and maritime organisations.

The Shom L range is distinguished by its folded format, which is particularly practical for route planning, coastal navigation and storage on board. Once unfolded, a Shom L chart generally provides a surface close to A0 size, while it is folded to approximately A4 size for easier handling and filing.

The Mediterranean, Black Sea and Sea of Marmara category covers a particularly extensive and varied maritime area: the French Mediterranean coast, Corsica, the Spanish Mediterranean coast, the Balearic Islands, Italy, Sardinia, Sicily, the Adriatic, Greece, the Aegean Sea, Turkey, the Sea of Marmara and, depending on the reference, areas used to prepare passages towards the Black Sea. The choice of chart therefore primarily depends on the precise area, scale and type of navigation planned.

A charting system suited to a highly diverse Mediterranean

The Mediterranean includes a succession of coastlines, islands, straits, gulfs, ports and navigation areas that differ considerably from one another. A passage between Marseille and Corsica does not require the same scale as an approach to Marseille, Toulon, Ajaccio or Bastia.

The Shom L charts therefore cover different levels of navigation. Some references are intended for coastal navigation and cover a relatively limited area at a scale that allows detailed reading. Others are more suitable for offshore navigation and the preparation of passages between different Mediterranean coastlines.

The areas represented in this category include in particular:

• the French Mediterranean coast;

• Marseille, the Calanques, Toulon and the French Riviera;

• Corsica and the Strait of Bonifacio;

• Sardinia and Sicily;

• the Balearic Islands;

• the Spanish Mediterranean coast;

• the Tyrrhenian Sea;

• the Ionian Sea;

• the Aegean Sea;

• the Greek and Turkish coasts;

• the Sea of Marmara;

• approaches to the Dardanelles and Bosphorus;

• the Black Sea, depending on the relevant chart coverage.

This diversity makes it particularly important to choose a Shom Mediterranean nautical chart with a scale appropriate to the intended navigation.

Major ports covered by the Mediterranean area

The charting of this region concerns a very large number of ports and anchorages. On the French coast, Marseille, Toulon, Nice, Cannes, Saint-Tropez, Port-Vendres, Sète, Port-la-Nouvelle, Bastia, Ajaccio, Calvi and Porto-Vecchio are important navigation points.

Further east, routes may involve Genoa, La Spezia, Livorno, Civitavecchia, Naples, Palermo, Cagliari, Olbia, Venice, Trieste, Split, Dubrovnik, Corfu, Athens, Piraeus, Rhodes, Izmir, Bodrum or Antalya.

In the straits and enclosed seas of the eastern Mediterranean, chart preparation becomes particularly important around Istanbul, the Bosphorus, the Sea of Marmara, the Dardanelles and the approaches to the Black Sea.

These examples do not mean that a single chart covers all of these ports. They simply illustrate the geographical extent of the area and the need to combine several charts when a route crosses different regions.

What information is shown on a Shom L nautical chart?

A Shom L nautical chart contains the information required to identify the represented maritime area and prepare a route. Depending on the scale and geographic area, it can be used to identify:

• depths and soundings;

• depth contours or isobaths;

• shoals and underwater hazards;

• rocks and wrecks;

• landmarks and coastal reference points;

• lights and their characteristics;

• buoys and other aids to navigation;

• channels and navigable waterways;

• ports and harbour facilities;

• anchorages;

• certain regulatory boundaries and special areas;

• information required to understand navigation within the area.

Reading a nautical chart nevertheless requires knowledge of the symbols, abbreviations and cartographic conventions used by Shom. A nautical chart should not be regarded as a simple geographical representation: it is designed to provide structured and prioritised nautical information.

Why choose a folded Shom L chart?

The main characteristic of the Shom L chart is its physical presentation. Unlike a Shom C chart, which is generally supplied flat and rolled, a Shom L chart is folded into several panels.

This format offers several advantages:

• easier storage on board;

• easier transport;

• convenient handling during route preparation;

• easier filing within a nautical documentation system;

• a large unfolded chart surface for viewing an extensive maritime area.

Once unfolded, a Shom L chart therefore retains a substantial cartographic surface while remaining compact when stored.

Differences between Shom C, L, G, Z and Raster charts

The main difference between Shom C and Shom L charts therefore concerns their physical presentation. Shom C charts are designed to be kept flat or rolled, whereas Shom L charts are folded to facilitate storage.

Shom G charts provide additional information concerning the nature of the seabed. They may distinguish different types of sediments and can be of particular interest for professional fishing, certain maritime activities or marine environmental studies.

Shom Z charts correspond to a specific variant incorporating information identifying exercise and firing areas. This information should be interpreted together with the relevant nautical and regulatory information.

Finally, the term Raster refers to a digital image representation. Georeferenced digital images of nautical charts should be distinguished from Shom RasterMarine products, which have their own conditions and limitations of use.

Choosing the correct scale for your navigation

Scale is one of the most important criteria when selecting a Mediterranean nautical chart.

A small-scale chart represents a large geographical area and is more suitable for passage planning or obtaining an overall view of a route. A large-scale chart represents a smaller area but provides more detail for coastal navigation or harbour approaches.

For a passage between two Mediterranean regions, an offshore chart may be appropriate for planning the overall route. When approaching a coast, archipelago, strait or harbour, larger-scale charts become necessary to obtain a more detailed representation.

For example, a passage between Marseille and Corsica may require different charting from that used for navigation through the Strait of Bonifacio or for preparing the approach to Marseille.

The Shom L Mediterranean range includes references covering different levels of scale. For example, some charts cover large Mediterranean sectors, such as reference 7204L between Marseille, Elba and the Strait of Bonifacio, while others are much more localised and cover Marseille, the Calanques, Toulon, Corsica or specific Mediterranean ports.

Navigation in the Mediterranean, Black Sea and Sea of Marmara

Navigation towards the eastern Mediterranean requires particular attention to chart continuity. A route linking France with Italy, Greece or Turkey crosses several hydrographic areas and may require several charts at different scales.

The Aegean Sea is particularly complex because of its large number of islands, channels and passages between land masses. The Sea of Marmara also has a distinctive configuration, particularly because of the strategic passages connecting the Dardanelles with the Bosphorus.

For a route continuing towards Istanbul and then the Black Sea, it is essential to check that the nautical documentation successively covers the different areas along the route, with appropriate scales for approaches and narrow passages.

Chart preparation is therefore not simply a matter of selecting a chart covering a large geographical area. It involves ensuring continuous and coherent chart coverage between the departure point, intermediate stops, coastal areas and harbour approaches.

Shom L charts and route planning

Before a Mediterranean passage, the paper chart makes it possible to visualise the entire route and identify major course changes, potentially difficult passages, islands, headlands, shoals and possible regulated areas.

It can also be used to prepare routes before departure and to maintain an independent cartographic reference alongside electronic systems.

Thorough preparation generally combines a chart at an appropriate scale with the necessary complementary nautical information and the applicable updates for the documentation being used.

Paper charts therefore retain an important role in route planning, even when a vessel is equipped with GPS, a chartplotter or electronic navigation software.

Charting for leisure sailors and professionals

Shom charts are not exclusively intended for recreational sailing. They can also be used in a variety of professional maritime contexts, depending on their coverage and scale.

They are of interest to:

• leisure sailors and yacht owners;

• motorboat crews;

• offshore navigators;

• merchant shipping professionals;

• commercial fishermen;

• maritime schools and training centres;

• navigation planners;

• delivery and passage crews;

• sailors undertaking international passages.

In the Mediterranean, this wide range of users explains why the chart range includes both extensive regional charts and highly detailed coastal charts.

Conclusion

The Shom L nautical chart range for the Mediterranean Sea, Black Sea and Sea of Marmara provides a paper charting solution suited to route planning and navigation in an extensive and complex maritime region. Its folded format facilitates transport and storage while retaining, once unfolded, a cartographic surface close to A0 size.

Choosing a Shom L chart should primarily take into account the geographical area, route, scale and type of navigation. A Mediterranean passage, coastal navigation in Corsica, an approach to Marseille, a route through the Aegean Sea or a passage towards the Sea of Marmara will not necessarily require the same references.

The Shom range therefore makes it possible to cover different charting requirements, from offshore passage planning to coastal navigation and harbour approaches. For navigation between the western and eastern Mediterranean, continuity between charts and consistency of scale are essential elements of route preparation.

FAQ – Shom L nautical charts for the Mediterranean Sea, Black Sea and Sea of Marmara

What is a Shom L nautical chart?

A Shom L chart is a folded paper nautical chart designed to be stored in an approximately A4 format. Once unfolded, it generally provides a chart surface close to A0 size and contains the nautical information required for navigation within the covered area.

What is the difference between a Shom C and a Shom L chart?

The main difference concerns the presentation. A Shom C is a flat paper chart, generally supplied rolled, whereas a Shom L is folded. Both provide standard nautical information, with coverage and scale depending on the individual reference.

Do Shom L charts cover the entire Mediterranean Sea?

The range includes numerous references covering different parts of the Mediterranean. A single chart will generally not cover the entire sea at a level of detail suitable for every purpose. The appropriate reference depends on the area and required scale.

Can a Shom L chart be used for navigation in Corsica?

Yes. Several Shom L references cover Corsica and its surrounding waters, including the areas around Bastia, Calvi, Ajaccio, Porto-Vecchio, Bonifacio and different sections of the Corsican coastline.

Which Shom chart should be used for a passage between Marseille and Corsica?

A chart whose scale and geographical coverage correspond to the planned passage should be selected, then supplemented with larger-scale charts for coastal and harbour approaches.

Do Shom L charts cover the Aegean Sea and Turkey?

The Mediterranean category includes different Mediterranean regions. For navigation towards Greece, Turkey, the Dardanelles or the Sea of Marmara, the geographical coverage of each individual reference should be checked carefully.

What is the difference between a Shom G and a Shom L chart?

A Shom G chart includes standard nautical charting while providing additional information concerning the nature and distribution of seabed sediments. It therefore serves different purposes from a standard Shom L chart.

What is a Shom Z chart used for?

A Shom Z chart includes an additional layer identifying relevant exercise and firing areas. It should be used together with the associated nautical and regulatory information.

What is a Shom Raster nautical chart?

It is a digital image representation of a nautical chart intended for certain compatible software applications. Shom distinguishes its digital raster nautical charts from RasterMarine products, which have specific uses and limitations.

What scale should be chosen for navigation in the Mediterranean?

The appropriate scale depends on the type of navigation. A small scale is more suitable for offshore passage planning and an overall view of a route, while a large scale is required for greater detail during coastal navigation or harbour approaches.

Which Mediterranean ports may be covered by Shom L charts?

Depending on the selected reference, chart coverage may include Marseille, Toulon, Cannes, Nice, Bastia, Ajaccio, Calvi, Porto-Vecchio, Bonifacio, Genoa, Naples, Palermo, Cagliari, Athens, Piraeus, Rhodes, Izmir or Istanbul.

Is a paper chart still useful when using GPS or a chartplotter?

Yes. A paper chart can be used to prepare a route, obtain an overall view of the area and maintain an independent cartographic reference alongside electronic equipment. It complements digital navigation tools rather than necessarily replacing them.