Limits vary by country:
France:• Base distance: 2 km maximum between furthest participants
• Possible extensions upon justified request:
- Rural area: up to 20 km
- Peri-urban area: up to 10 km
- Urban area: maintained at 2 km
• Classification based on INSEE municipal density grid
Belgium:• Wallonia: perimeter limited to municipality or behind high voltage cabin
• Flanders: no strict geographical limit in the region
• Brussels: mandatory legal entity, perimeter defined by project
