What is the oldest open problem in mathematics ? By old, I am refering to the date the problem was stated.
Browsing wikipedia list of open problems, it seems that the Goldbach conjecture (1742, every even integer greater than 2 is the sum of two primes) is a good candidate.
The Kepler conjecture about sphere packing is from 1611 but I think this is finally solved (anybody confirms ?). There may still be some open problem stated at that time on the same subject, that is not solved. Also there are problems about cuboids that Euler may have stated and are not yet solved, but I am not sure about that.
A related question: can we say that we have solved all problems handed down by the mathematicians from Antiquity ?