3. After S Swordy (Chicago)

7. Trans-GZK event detected at Haverah Park

8. Heck et al. Hamburg Conference 2001

9. Schematic idea of Fly’s Eye Detector (University of Utah)

10. Largest Fly’s Eye event: 3 x 10^20 eV

11. Results of AGASA group: Hamburg 2001

12. Summary of Spectrum post-Hamburg 2001

14. Arrival Direction Data of AGASA Group

20. Ave et al. Astroparticle Physics 14 91 2000

21. Ave et al. PRL

22. Comparison of Haverah Park photon limit with theory

24. Diagram by Enrique Zas (Santiago de Compostela)

26. Picture by Peter Walker

28. First threefold signal from Auger Surface Detector

29. Working on a tank in the Pampa

30. Aperture and camera of FD system at Los Leones

31. An early event in the fluorescence detector

32. Conclusions
There are many reasons to be intrigued by the highest energy cosmic rays that justify discussion of this topic at a meeting entitled ‘Particle Physics at the Limits’
Large increases in data and fresh particle physics input are needed.
The Engineering Array of the Pierre Auger Observatory has been operated sucessfully.