A problem in Graph Theory requiring the most efficient (i.e., least total distance) Tour (i.e., closed path) a salesman can take through each of cities. No general method of solution is known, and the problem is NP-Hard.

**References**

Platzman, L. K. and Bartholdi, J. J. ``Spacefilling Curves and the Planar Travelling Salesman Problem.''
*J. Assoc. Comput. Mach.* **46**, 719-737, 1989.

© 1996-9

1999-05-26