diff --git a/app/controllers/instructeurs/dossiers_controller.rb b/app/controllers/instructeurs/dossiers_controller.rb
index a7a7d9c4c..c88e4108d 100644
--- a/app/controllers/instructeurs/dossiers_controller.rb
+++ b/app/controllers/instructeurs/dossiers_controller.rb
@@ -19,6 +19,12 @@ module Instructeurs
       end
     end
 
+    def geo_data
+      send_data dossier.to_feature_collection.to_json,
+        type: 'application/json',
+        filename: "dossier-#{dossier.id}-features.json"
+    end
+
     def apercu_attestation
       @attestation = dossier.procedure.attestation_template.render_attributes_for(dossier: dossier)
 
diff --git a/app/models/champ.rb b/app/models/champ.rb
index 9e2c2cf63..7f2974db0 100644
--- a/app/models/champ.rb
+++ b/app/models/champ.rb
@@ -86,6 +86,10 @@ class Champ < ApplicationRecord
     true
   end
 
+  def stable_id
+    type_de_champ.stable_id
+  end
+
   private
 
   def needs_dossier_id?
diff --git a/app/models/champs/carte_champ.rb b/app/models/champs/carte_champ.rb
index 7d54d9880..6bdc54f9e 100644
--- a/app/models/champs/carte_champ.rb
+++ b/app/models/champs/carte_champ.rb
@@ -74,7 +74,7 @@ class Champs::CarteChamp < Champ
   def to_feature_collection
     {
       type: 'FeatureCollection',
-      id: type_de_champ.stable_id,
+      id: stable_id,
       bbox: bounding_box,
       features: (legacy_selections_utilisateur + except_selections_utilisateur).map(&:to_feature)
     }
diff --git a/app/models/champs/repetition_champ.rb b/app/models/champs/repetition_champ.rb
index 9105000aa..dbad478c4 100644
--- a/app/models/champs/repetition_champ.rb
+++ b/app/models/champs/repetition_champ.rb
@@ -35,7 +35,7 @@ class Champs::RepetitionChamp < Champ
 
   # We have to truncate the label here as spreadsheets have a (30 char) limit on length.
   def libelle_for_export
-    str = "(#{type_de_champ.stable_id}) #{libelle}"
+    str = "(#{stable_id}) #{libelle}"
     # /\*?[] are invalid Excel worksheet characters
     ActiveStorage::Filename.new(str.delete('[]*?')).sanitized.truncate(30)
   end
diff --git a/app/models/dossier.rb b/app/models/dossier.rb
index b47cc927f..5aeb5c359 100644
--- a/app/models/dossier.rb
+++ b/app/models/dossier.rb
@@ -700,8 +700,36 @@ class Dossier < ApplicationRecord
     { id: self.id, procedure_libelle: self.procedure.libelle }
   end
 
+  def geo_data?
+    geo_areas.present?
+  end
+
+  def to_feature_collection
+    {
+      type: 'FeatureCollection',
+      id: id,
+      bbox: bounding_box,
+      features: geo_areas.map(&:to_feature)
+    }
+  end
+
   private
 
+  def geo_areas
+    champs.includes(:geo_areas).flat_map(&:geo_areas) + champs_private.includes(:geo_areas).flat_map(&:geo_areas)
+  end
+
+  def bounding_box
+    factory = RGeo::Geographic.simple_mercator_factory
+    bounding_box = RGeo::Cartesian::BoundingBox.new(factory)
+
+    geo_areas.each do |area|
+      bounding_box.add(area.rgeo_geometry)
+    end
+
+    [bounding_box.max_point, bounding_box.min_point].compact.flat_map(&:coordinates)
+  end
+
   def log_dossier_operation(author, operation, subject = nil)
     if log_operations?
       DossierOperationLog.create_and_serialize(
diff --git a/app/models/geo_area.rb b/app/models/geo_area.rb
index 510dc3b75..604a37c3e 100644
--- a/app/models/geo_area.rb
+++ b/app/models/geo_area.rb
@@ -36,7 +36,14 @@ class GeoArea < ApplicationRecord
     {
       type: 'Feature',
       geometry: geometry,
-      properties: properties.merge(source: source, area: area, length: length).compact
+      properties: properties.symbolize_keys.merge(
+        source: source,
+        area: area,
+        length: length,
+        id: id,
+        champ_id: champ.stable_id,
+        dossier_id: champ.dossier_id
+      ).compact
     }
   end
 
diff --git a/app/views/instructeurs/dossiers/_header_actions.html.haml b/app/views/instructeurs/dossiers/_header_actions.html.haml
index eaa46936f..4a65d92f9 100644
--- a/app/views/instructeurs/dossiers/_header_actions.html.haml
+++ b/app/views/instructeurs/dossiers/_header_actions.html.haml
@@ -8,6 +8,9 @@
       = link_to "Uniquement cet onglet", "#", onclick: "window.print()", class: "menu-item menu-link"
     %li
       = link_to "Export PDF", instructeur_dossier_path(dossier.procedure, dossier, format: :pdf), target: "_blank", rel: "noopener", class: "menu-item menu-link"
+    - if dossier.geo_data?
+      %li
+        = link_to "Export GeoJSON", geo_data_instructeur_dossier_path(dossier.procedure, dossier), target: "_blank", rel: "noopener", class: "menu-item menu-link"
 
 - if !PiecesJustificativesService.liste_pieces_justificatives(dossier).empty?
   %span.dropdown.print-menu-opener
diff --git a/app/views/shared/dossiers/editable_champs/_carte.html.haml b/app/views/shared/dossiers/editable_champs/_carte.html.haml
index 4399929b6..c7c058056 100644
--- a/app/views/shared/dossiers/editable_champs/_carte.html.haml
+++ b/app/views/shared/dossiers/editable_champs/_carte.html.haml
@@ -10,4 +10,4 @@
   = render partial: 'shared/champs/carte/geo_areas', locals: { champ: champ, error: false }
 
 = form.hidden_field :value,
-  data: { remote: true, feature_collection_id: champ.type_de_champ.stable_id, url: champs_carte_path(form.index), params: champ_carte_params(champ).to_query, method: 'post' }
+  data: { remote: true, feature_collection_id: champ.stable_id, url: champs_carte_path(form.index), params: champ_carte_params(champ).to_query, method: 'post' }
diff --git a/config/routes.rb b/config/routes.rb
index 4e5648a8d..ba024c094 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -316,6 +316,7 @@ Rails.application.routes.draw do
         resources :dossiers, only: [:show], param: :dossier_id do
           member do
             get 'attestation'
+            get 'geo_data'
             get 'apercu_attestation'
             get 'messagerie'
             get 'annotations-privees' => 'dossiers#annotations_privees'
diff --git a/spec/factories/geo_area.rb b/spec/factories/geo_area.rb
index 12e87c679..406844ef3 100644
--- a/spec/factories/geo_area.rb
+++ b/spec/factories/geo_area.rb
@@ -1,8 +1,10 @@
 FactoryBot.define do
   factory :geo_area do
-    source { GeoArea.sources.fetch(:cadastre) }
-    numero { '42' }
-    feuille { 'A11' }
+    trait :cadastre do
+      source { GeoArea.sources.fetch(:cadastre) }
+      numero { '42' }
+      feuille { 'A11' }
+    end
 
     trait :quartier_prioritaire do
       source { GeoArea.sources.fetch(:quartier_prioritaire) }
@@ -13,5 +15,25 @@ FactoryBot.define do
     trait :selection_utilisateur do
       source { GeoArea.sources.fetch(:selection_utilisateur) }
     end
+
+    trait :polygon do
+      geometry do
+        {
+          "type": "Polygon",
+          "coordinates": [
+            [
+              [2.428439855575562, 46.538476837725796],
+              [2.4284291267395024, 46.53842148758162],
+              [2.4282521009445195, 46.53841410755813],
+              [2.42824137210846, 46.53847314771794],
+              [2.428284287452698, 46.53847314771794],
+              [2.428364753723145, 46.538487907747864],
+              [2.4284291267395024, 46.538491597754714],
+              [2.428439855575562, 46.538476837725796]
+            ]
+          ]
+        }
+      end
+    end
   end
 end
diff --git a/spec/models/dossier_spec.rb b/spec/models/dossier_spec.rb
index 996c409bc..1d53de91e 100644
--- a/spec/models/dossier_spec.rb
+++ b/spec/models/dossier_spec.rb
@@ -1234,4 +1234,34 @@ describe Dossier do
     it { expect(procedure).not_to be_nil }
     it { expect(procedure.discarded?).to be_truthy }
   end
+
+  describe "to_feature_collection" do
+    let(:geo_area) { create(:geo_area, :selection_utilisateur, :polygon) }
+    let(:champ) { create(:champ_carte, geo_areas: [geo_area]) }
+    let(:dossier) { create(:dossier, champs: [champ]) }
+
+    it 'should have all champs carto' do
+      expect(dossier.to_feature_collection).to eq({
+        type: 'FeatureCollection',
+        id: dossier.id,
+        bbox: [2.428439855575562, 46.538491597754714, 2.42824137210846, 46.53841410755813],
+        features: [
+          {
+            type: 'Feature',
+            geometry: {
+              'coordinates' => [[[2.428439855575562, 46.538476837725796], [2.4284291267395024, 46.53842148758162], [2.4282521009445195, 46.53841410755813], [2.42824137210846, 46.53847314771794], [2.428284287452698, 46.53847314771794], [2.428364753723145, 46.538487907747864], [2.4284291267395024, 46.538491597754714], [2.428439855575562, 46.538476837725796]]],
+              'type' => 'Polygon'
+            },
+            properties: {
+              area: 219.0,
+              champ_id: champ.stable_id,
+              dossier_id: dossier.id,
+              id: geo_area.id,
+              source: 'selection_utilisateur'
+            }
+          }
+        ]
+      })
+    end
+  end
 end
diff --git a/spec/serializers/champ_serializer_spec.rb b/spec/serializers/champ_serializer_spec.rb
index 97a6712f4..54af2b224 100644
--- a/spec/serializers/champ_serializer_spec.rb
+++ b/spec/serializers/champ_serializer_spec.rb
@@ -26,7 +26,7 @@ describe ChampSerializer do
     context 'when type champ is carte' do
       let(:champ) { create(:champ_carte, value: value, geo_areas: [geo_area].compact) }
       let(:value) { nil }
-      let(:geo_area) { create(:geo_area, geometry: geo_json) }
+      let(:geo_area) { create(:geo_area, :cadastre, geometry: geo_json) }
       let(:geo_json) do
         {
           "type" => 'MultiPolygon',