I done it in my car, mensroom, work, woods, at a party with 4 other guys.

Driving up the Florida turnpike, sitting in parking lot during lunch break, on a bus during a church outing (i was alone on the bus but they could've came any minute)

I answered this a few times before Mine was on a plywood 4 hole toilet on Hill 55 15 miles southwest of Danang during incoming small arms fire. After getting off I returned to my work space less stressed and more upbeat.

In a ladies restroom! I thought I wouldn't get interrupted but just as I was getting to the point of no return someone came in to the stall next to me. I heard her pulling up her skirt and pulling down her knickers and I shot my load as she was pissing!

Damn. You're literally a trooper

I've answered this before but:

Cars, trains, buses, boats, parties with other guys, boardroom table at work, and on my neighbour's doorstep!

Having grown up in Southern California, not far from the original Disneyland, my friends and I usually visited once a week during the summers all through my teenage years. By myself, or sometimes with them, I/We jerked off on Tom Sawyers Island (lot's of places there,) the Mad Hatter Ride, the Haunted Mansion ride and best of all the Sleeping Beauty Castle walk through (a good chance of getting "caught" by girls ...)

I've jerked off in a lot of weird places but the weirdest was probably a house under construction. There was a development going up not too far from my place and I drove by it one night one night around 3AM and parked next to one of the houses. The back sliding door was unlocked when I tried it so I went in. I stripped naked and walked all through the house jerking off. I came in the upstairs would-be master bedroom. Best jerking experience ever.

In my friend's bedroom while she was out of town, wearing her lingerie and smelling the dirty panties she has left on the floor. Don't tell!