This example can be solved using just subtour-elimination constraints. The optimal TSP value is 29,766.

This 29-city instance is based on the WI29 example from the National TSPs collection of test instances. The subset of permitted edges was created by taking the Delaunay triangulation of the 29 cities and removing several long edges along the border of the point set. The points were modified slightly from the original example in order to more easily visualize the connections between the cities.