  The Pierre Auger Observatory is a multi-national project for research on
ultra-high energy cosmic rays. The Southern Auger Observatory in Mendoza
province, Argentina, is approaching completion in 2007 with an instrumented
area of 3,000 km^2. It will accurately measure the spectrum and composition of
ultra-high energy cosmic rays up to and beyond the predicted GZK feature. We
are obtaining results on the energy spectrum, mass composition and distribution
of arrival directions on the southern sky. The Northern Auger Observatory is
designed to complete and extend the investigations begun in the South. It will
establish charged particle astronomy and thus open a new window into the
universe. The distribution of arrival directions of the highest energy events
will point the way to unveiling the almost century old mystery of the origin
and nature of ultra-high energy cosmic rays. Achieving this goal requires
collecting many more events in spite of the steeply falling energy spectrum.
The planned northern site will have an instrumented area of 4,000 square miles
(10,370 km}^2 in Southeast Colorado, USA. The paper covers the science of
charged particle astronomy, the layout and the technical implementation of the
Northern Auger Observatory.
