Cannon are legal under federal law and in most states. You may have to jump through a few hoops to get one, but get one you assuredly can.
If it's legal to buy an AR-15 in America, why can't you buy a tank? You can! John Blumenthal
Greenfield police negotiate a ceasefire with resident Frank Markel regarding his Independence Day cannon firing celebration
MSFS vehicles never fail to ruin the immersion, had a laugh with
Can't see a Caesar and not want a Caesar : r/Letterkenny
Time to break out the patio set : r/funny
Civil War Cannon Rebel Flag Zip Pouch by Randy Steele - Fine Art America
Peter Carried a Cannon, The Real Story – Emerging Revolutionary War Era
Seen in Roadhouse north of Brisbane : r/australia
Weird Law: It's Legal to Own a Cannon in New York? What?