On November 25, 1783, General George Washington, mounted on a white charger, marched the Continental Army into New York City as the last British troops in that city evacuated. For many years, this event would be remembered as Evacuation Day, an important holiday in New York City for more than a century.
When General Washington dismounted from his horse, where would he have parked it?
Where would you park a horse--that is, tie it off and leave it alone--now?
Rhett Jones of Hopes & Fears thoroughly researched that question. As you might expect, NYPD cops can park their horses with great leeway. But what about those of us without government privileges? Jones eventually tracked down an answer in the New York City Traffic Rules, section 4-12.f, which says:
No person shall leave a horse unbridled or unattended in a street or unenclosed place unless the horse is securely fastened, or harnessed to a vehicle with wheels so secured as to prevent it from being dragged faster than a walk.
So, basically, you just need a solid hitching post.