The Marseille Tide Gauge and the JB200
A modest edifice, a historic mission
On the Corniche Kennedy in Marseille, a small stone building stands facing the Mediterranean, offering a panoramic view that stretches from Estaque to the Calanques. Few passersby notice it.
Yet, it is here — and nowhere else in France — that the reference point from which all altitudes in the country are measured is located.
The Marseille Tide Gauge is not a spectacular monument. It is not tall, nor ornate, nor focused on appearance. It is a scientific instrument, designed to measure the mean sea level with absolute precision — and to measure it continuously, for over 140 years.
1883 — the year Marseille becomes the reference
The building was constructed in 1883 and later entrusted to the IGN, the French National Institute of Geographic and Forest Information, which remains its owner today. Its mission is clear: to measure the mean level of the Mediterranean Sea with unparalleled scientific rigor, and to set the official zero of French altitudes based on this measurement.
From sea level to the peaks of the Alps, from the Old Port quay to the summit of Mont Blanc — every altitude in mainland France is calculated from this point. An invisible line, drawn at the level of Marseille's soil, which has structured all the country's maps for over a century.
Why the Mediterranean, and not the Atlantic
The question may be surprising. Atlantic sailors, accustomed to tides of several meters, may be astonished that a tide gauge was installed in the Mediterranean — a sea with modest tidal range. But it is precisely this stability that motivated the choice of Marseille.
A sea with discreet tides allows for a purer measurement, less noisy due to extreme amplitudes. To set a reference zero — a point that is not debatable — a calm, readable sea was needed, whose variations fall within a regularity accessible to the instrument. Marseille imposed itself by this stability, not despite it.
A climate witness for over a century
Since 1883, the Tide Gauge has continuously traced the sea level curve. It is one of the longest continuous recordings in the world — and one of the most valuable data available to contemporary science for understanding the climate.
The observation is irrefutable: since the end of the 19th century, the mean level of the Mediterranean Sea has risen by approximately 18 centimeters at the Marseille point. A measurement made possible by the absolute regularity of the instrument, and which today constitutes one of the scientific bases for studying global warming in France.
The JB200 Marégraphe — a dial that tells altitude
It is this building — discreet, rigorous, foundational — that the JB200 Marégraphe honors. Launched on August 21, 2024, in a limited edition of 150 numbered pieces, it was born from a direct collaboration with the IGN, owner of the building.
The azure blue dial reproduces, on its surface, the contour lines of nautical charts — these topographic lines that delineate underwater and terrestrial reliefs. More than a decorative motif, this design is a direct tribute to the very function of the Tide Gauge: to measure altitude, to set the reference, to read the relief. Beyond aesthetics, these lines produce unexpected plays of light under the Mediterranean sun.
The red 24-hour marking — a nod to the brand's vintage models — and the oversized "Maxi Dial" indices ensure perfect readability. The case back is engraved with the stylized silhouette of the Tide Gauge: the watch carries on its back, engraved in steel, the building it celebrates.
First crown on the right: a deliberate break
The JB200 Marégraphe marks an unexpected turning point in the brand's history. For the first time, the setting crown is positioned on the right side of the dial — a break with the "destro" tradition (crown on the left) that had previously characterized JB200 models.
A choice that is not neutral. The brand, until then faithful to the configuration inherited from 1980s military watches, is opening a new ergonomic path here. More than just a change of position, it is a statement: a brand's identity extends by evolving, and the JB200 Marégraphe inaugurates this possibility.
A partnership with the IGN, a donation to the Friends of the Tide Gauge
Beyond the aesthetic tribute, the JB200 Marégraphe is driven by a concrete commitment. A portion of the profits from the limited edition was donated to the Association des Amis du Marégraphe (Friends of the Tide Gauge Association), dedicated to promoting the edifice and raising awareness of environmental issues related to rising sea levels.
On September 16, 2024, in Marseille, the brand officially presented the association with a check for €11,115, taken from the sales of the JB200 Marégraphe.
Pay against this check: Eleven Thousand One Hundred and Fifteen Euros To: Les Amis du Marégraphe Made in Marseille, September 16, 2024
A sum dedicated to the preservation of the building, the promotion of its scientific role, and public awareness of the climate issues that the instrument has documented for over 140 years. A way for the brand to serve a heritage that goes beyond watchmaking — a French scientific heritage, rooted in Marseille, whose voice is heard in the contemporary climate debate.
A promise from Marseille
Since its founding by Greek colonists from Phocaea around 600 BC, Marseille has always maintained an intimate relationship with the sea and with time. The Tide Gauge is its most precise, discreet, and enduring expression.
With the JB200 Marégraphe, Jacques Bianchi Marseille pays tribute to this continuity — where the sea measures time, where the city keeps track, where a watch can be both an object and a landmark.
Limited edition of 150 numbered pieces. Price: €890 incl. VAT. A portion of the profits donated to the Association des Amis du Marégraphe. Item now sold out.
The Marseille Tide Gauge
The Marseille Tide Gauge and the JB200
A modest edifice, a historic mission
On the Corniche Kennedy in Marseille, a small stone building stands facing the Mediterranean, offering a panoramic view that stretches from Estaque to the Calanques. Few passersby notice it.
Yet, it is here — and nowhere else in France — that the reference point from which all altitudes in the country are measured is located.
The Marseille Tide Gauge is not a spectacular monument. It is not tall, nor ornate, nor focused on appearance. It is a scientific instrument, designed to measure the mean sea level with absolute precision — and to measure it continuously, for over 140 years.
1883 — the year Marseille becomes the reference
The building was constructed in 1883 and later entrusted to the IGN, the French National Institute of Geographic and Forest Information, which remains its owner today. Its mission is clear: to measure the mean level of the Mediterranean Sea with unparalleled scientific rigor, and to set the official zero of French altitudes based on this measurement.
From sea level to the peaks of the Alps, from the Old Port quay to the summit of Mont Blanc — every altitude in mainland France is calculated from this point. An invisible line, drawn at the level of Marseille's soil, which has structured all the country's maps for over a century.
Why the Mediterranean, and not the Atlantic
The question may be surprising. Atlantic sailors, accustomed to tides of several meters, may be astonished that a tide gauge was installed in the Mediterranean — a sea with modest tidal range. But it is precisely this stability that motivated the choice of Marseille.
A sea with discreet tides allows for a purer measurement, less noisy due to extreme amplitudes. To set a reference zero — a point that is not debatable — a calm, readable sea was needed, whose variations fall within a regularity accessible to the instrument. Marseille imposed itself by this stability, not despite it.
A climate witness for over a century
Since 1883, the Tide Gauge has continuously traced the sea level curve. It is one of the longest continuous recordings in the world — and one of the most valuable data available to contemporary science for understanding the climate.
The observation is irrefutable: since the end of the 19th century, the mean level of the Mediterranean Sea has risen by approximately 18 centimeters at the Marseille point. A measurement made possible by the absolute regularity of the instrument, and which today constitutes one of the scientific bases for studying global warming in France.
The JB200 Marégraphe — a dial that tells altitude
It is this building — discreet, rigorous, foundational — that the JB200 Marégraphe honors. Launched on August 21, 2024, in a limited edition of 150 numbered pieces, it was born from a direct collaboration with the IGN, owner of the building.
The azure blue dial reproduces, on its surface, the contour lines of nautical charts — these topographic lines that delineate underwater and terrestrial reliefs. More than a decorative motif, this design is a direct tribute to the very function of the Tide Gauge: to measure altitude, to set the reference, to read the relief. Beyond aesthetics, these lines produce unexpected plays of light under the Mediterranean sun.
The red 24-hour marking — a nod to the brand's vintage models — and the oversized "Maxi Dial" indices ensure perfect readability. The case back is engraved with the stylized silhouette of the Tide Gauge: the watch carries on its back, engraved in steel, the building it celebrates.
First crown on the right: a deliberate break
The JB200 Marégraphe marks an unexpected turning point in the brand's history. For the first time, the setting crown is positioned on the right side of the dial — a break with the "destro" tradition (crown on the left) that had previously characterized JB200 models.
A choice that is not neutral. The brand, until then faithful to the configuration inherited from 1980s military watches, is opening a new ergonomic path here. More than just a change of position, it is a statement: a brand's identity extends by evolving, and the JB200 Marégraphe inaugurates this possibility.
A partnership with the IGN, a donation to the Friends of the Tide Gauge
Beyond the aesthetic tribute, the JB200 Marégraphe is driven by a concrete commitment. A portion of the profits from the limited edition was donated to the Association des Amis du Marégraphe (Friends of the Tide Gauge Association), dedicated to promoting the edifice and raising awareness of environmental issues related to rising sea levels.
On September 16, 2024, in Marseille, the brand officially presented the association with a check for €11,115, taken from the sales of the JB200 Marégraphe.
A sum dedicated to the preservation of the building, the promotion of its scientific role, and public awareness of the climate issues that the instrument has documented for over 140 years. A way for the brand to serve a heritage that goes beyond watchmaking — a French scientific heritage, rooted in Marseille, whose voice is heard in the contemporary climate debate.
A promise from Marseille
Since its founding by Greek colonists from Phocaea around 600 BC, Marseille has always maintained an intimate relationship with the sea and with time. The Tide Gauge is its most precise, discreet, and enduring expression.
With the JB200 Marégraphe, Jacques Bianchi Marseille pays tribute to this continuity — where the sea measures time, where the city keeps track, where a watch can be both an object and a landmark.
Limited edition of 150 numbered pieces. Price: €890 incl. VAT. A portion of the profits donated to the Association des Amis du Marégraphe. Item now sold out.