Henry Ernest Dudeney/Puzzles and Curious Problems/261 - The Twenty-Two Bridges

Puzzles and Curious Problems by Henry Ernest Dudeney: $261$

The Twenty-Two Bridges

We have a rough map of a district with an elaborate system of irrigation,

as the various waterways and numerous bridges will show.

A man set out from one of the lettered departments to pay a visit to a friend living in a different department.

For the purpose of pedestrian exercise he crossed every one of the bridges once, and once only.

The puzzle is to show in which two departments their houses are situated.

It is exceedingly easy if you give it a few moments' thought.

You must not go outside the borders of the diagram.

Sources

• 1932: Henry Ernest Dudeney: Puzzles and Curious Problems ... (previous) ... (next): Unicursal and Route Problems: $261$. -- The Twenty-Two Bridges
• 1968: Henry Ernest Dudeney: 536 Puzzles & Curious Problems ... (previous) ... (next): Combinatorial & Topological Problems: Route & Network Puzzles: $419$. The Twenty-Two Bridges