  The Traveling Tournament Problem (TTP) is a challenging combinatorial
optimization problem that has attracted the interest of researchers around the
world. This paper proposes an improved search neighbourhood for the TTP that
has been tested in a simulated annealing context. The neighbourhood encompasses
both feasible and infeasible schedules, and can be generated efficiently. For
the largest TTP challenge problems with up to 40 teams, solutions found using
this neighbourhood are the best currently known, and for smaller problems with
10 teams, three solutions found were subsequently proven optimal.
