Andorra and Spain Remeasure 150-Year-Old Border with GNSS Tech

Andorra and Spain are using high-precision technology to review their shared border, originally marked over 150 years ago, amid discrepancies uncovered in recent years.

The process began in 2021 after Catalan rural agents reported that the solar park at Planell de la Tosa in Pal Arinsal encroached on land mapped as Spanish territory in Alt Urgell. Around 16,000 of the facility's 22,000 square metres lie in the disputed area. This incident highlighted longstanding ambiguities along Andorra's southern flank, leading to the formation of a joint Hispano-Andorran commission in 2022.

Technicians from Andorra's Ministries of Foreign Affairs and Territory are collaborating with specialists from Spain's National Geographic Institute and the Army's Geographic Centre. They are remeasuring boundary markers—small crosses carved into rocks, spaced by distances recorded in castilian varas, a unit equating to 83.59 centimetres. These were set between 1856 and 1863 via a notarial act signed by Andorran notary Rossend Jordana and Salvador Galindo from La Seu d'Urgell, paralleling the Treaty of Bayonne that defined the Pyrenean border between Spain and France.

Using GNSS technology, teams have recalculated these spans with errors under five centimetres, uncovering moss-covered or eroded markers. The review does not automatically alter the border but provides a far more accurate tracing.

Disputed areas total nearly 200 hectares. At Coll de Laquell, between Sant Julià de Lòria and Civís, 80.71 hectares remain unresolved. Near the southern slope of Pic de Montmalús, between Encamp and Lles de Cerdanya, another 76.56 hectares are in question. Southwest of Pic Negre, between Escaldes-Engordany and Bescaran, 29.88 hectares complete the set. Many zones hold economic or environmental value, including forest tracks, hunting grounds, and energy projects.

Historically, the border's first documented mention dates to 1007 in a donation by the Count of Urgell. For centuries, boundaries functioned more as shared communal spaces than rigid sovereignty lines. A precedent exists with France: in 2012, after decades of talks sparked by incidents at Estany de les Abelletes, the two sides settled 46.61 hectares definitively.

The current effort aims to convert this tradition-based frontier into a legally robust, technically precise demarcation agreeable to both nations.