Tunnel Shapes In Dog Agility Course Design
13 Aug 2026
First Draft!
Some of these thoughts are already part of some organization’s agility course design guidelines, but I wanted to share my perspective on tunnel shapes:
Tunnels must be drawn stretched to their full length.
Tunnel shapes must be uniform curves; like the arc of a circle. Don’t design using “C”, “S”, “L”, or “J” shaped tunnels. A gentle curve can usually be substituted for these shapes with some creativity.
10ft/3m tunnels and shorter should only be used in a straight line. When curved there have been large dogs not seeing how short the these tunnels are and misjudging the length, resulting in the dog placing their last stride outside of the tunnel and sliding sideways on the ground.
I believe agility course design software should enforce these rules. Minimally, they should not allow tunnels to be shortened from their maximum length.
Thankfully, many course designers are already following these rules, but I still see some courses that use “C”, “S”, “L”, and “J” shaped tunnels.
My Agility Course Master software uses computer vision to detect tunnel shapes from course maps. AC Master always displays tunnels at their full length. It excludes “S”, “L” and “J” shaped tunnels; replacing them with the closest fitting curve. But it still matches and displays “C” shaped tunnels because there are so many AKC courses that use them.
I’ve created this table showing the tunnel shapes matched by AC Master and highlighted the background of shapes in green that I believe are acceptable for use in agility courses.
AC Master Tunnel Shapes
| Shape | 3ft/1m | 5ft/2m | 10ft/3m | 12ft/4m | 15ft/5m | 20ft/6m |
|---|---|---|---|---|---|---|
| Straight | ||||||
| 15° | ||||||
| 33° | ||||||
| 50° | ||||||
| 69° | ||||||
| 88° | ||||||
| 108° | ||||||
| 130° | ||||||
| 151° | ||||||
| 180° | ||||||
With some help from agility friends I’ve extracted the rules for the tightest curves allowed by some organizations’ rules and show them below.
Agility Nexus Maximum Curves
Tunnels shorter than 5 meters are not allowed to be curved under Agility Nexus rules.
5.0 m tunnel
6.0 m tunnel
UKI Maximum Curves
Tunnels shorter than 15 ft are not allowed to be curved under UKI rules.
15 ft tunnel
20 ft tunnel
USDAA Maximum Curves
15 ft tunnel
20 ft tunnel
So this is my attempt to improve the shape of tunnels we see in agility courses. The tighter the curve, the more difficult it is for dogs to navigate, and the more likely they are to get injured. Hopefully judges will use this information to improve the safety of the courses they design, even if all organizations don’t adopt the same rules.
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