Guédelon Castle Project Overview

• Medieval castle construction in France for 25+ years
• Using historically accurate 13th century plans and techniques
• Experimental archeology + tourist attraction
• Techniques now helping Notre Dame Cathedral reconstruction
• Project timeline: Started 1228, currently year 1253 (moving forward annually)
• Completion expected in ~10 years (35 years total construction time)
  • Longer than actual Middle Ages due to educational demonstrations
  • Workers spend half time explaining work to visitors

Historical Research Methodology

• Sources: illuminated manuscripts, stained glass windows, financial records
• Collaboration with archeologists, art historians, castellologists
• Some skills never lost, others completely lost and revived from scratch
• Focus specifically on 13th century technology

Castle Design and Purpose

• Built for low-ranking local nobleman (not royal castle)
• Private home with defensive elements
• Features: portcullis, defensive walls
• Defensive features included despite low attack probability in mid-13th century

Treadmill Crane Technology

• Technology dates back to Roman times
• Used in 13th century cathedral construction
• Historical evidence: medieval cranes still exist in cathedral roof timbers
  • Canterbury Cathedral has wonderful example
• Two types at Guédelon:
  • Single drum winch: 250kg (550lb) capacity, one person operation
  • Double drum winch: 500kg (1,000lb) capacity, 360° pivot capability
    • Can hoist from quarry and rotate to place exactly on masonry

Safety Modifications

• 21st century health and safety standards applied
• Anachronisms on site: hard hats, steel toe shoes, protective eyewear, masks for sandstone work
• Heavily reinforced scaffolding
• Modern brake system added (no evidence of braking on medieval cranes)
• Not trying to discover medieval injury/death rates

Crane Operation Process

• Carefully managed three-person operation:
  • One person responsible for brakes
  • One person at base charging cradle
  • One person overseeing entire operation (monitoring walker progress)
• Walker inside machine can't see, requires coordination
• Daily capacity: ~3 metric tonnes hoisted

Personal Experience Operating Crane

• Lifted 150-200kg load
• Technique: look at fixed points to avoid dizziness
• Feedback loop: faster walking → faster turning → faster pushing back
• Risk of hitting head on rear axle
• Like walking up steep hill with mechanical advantage ratio similar to 5 flights of stairs (10 meters horizontal = 1 meter vertical)