![A photo showing Border Patrol agents exploring the tunnel](/sites/default/files/photo/10.%20Tunnel-Douglas%2C%20AZ-JD_1.jpg)
The Douglas Tunnel is an example of a sophisticated tunnel which required significant engineering to complete.
This page was published more than five years ago. Information on the page may be out of date.
The Douglas Tunnel is an example of a sophisticated tunnel which required significant engineering to complete.