While the Freedom tower, replacing the WTC twin towers, is being constructed at ground zero, I still enjoy looking at some of the earlier submitted proposals. They tend to be more elementary, serene, elegant or characteristic than the final design, which had to deal with all the practicalities and compromises between all the stakeholders.
Especially Lars Spuybroek's (NOX) proposal Oblique, created shortly after the WTC attacks, is like a schoolbook illustration showing the differences between the 20th century architecture and the architecture of our time. Spuybroek envisions a swirling cluster of porous towers rising from Ground Zero, lifting the street into the sky, while allowing sunlight to the street level: 'Elevators form a highly complex structure of diagonals where at some platforms more than five or six different cores come together to form larger public areas. It is this network of elevators which makes the buildings not just a new type of tower, but more like a new type of urbanism.'
Twice the same building, but in a different era. Both illustrative for their time.