It's technically the law that they must be on leash.
The common etiquette for waling dogs in all public areas is to install a leash on your dog. Yes some people get offended.
There are signs saying they must be on leash, but there are many well-behaved dogs (and equally well-behaved owners) on the trail without leashes.
It's best to have dogs leashed but it's your Call. :) some people do walk their dogs without the leash but I know most people prefer people to do that but use your best judgement my friend and enjoy!
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