Spitbank Fort Southsea I parked in the local parking area. There are lots of free parking however you are limited to two hours.
The originator declared that this location was not inside a Flight Restriction Zone at the time of being flown on 11/07/2021. It remains the responsibility of any pilot to check for any changes before flying at the same location.
I’ve easily managed two rounds trips to the fort on one battery. I was flying the Mavic Pro that has a shorter total flight time, so you have no worries with the Mini 3 Pro for a single trip.
Edit: Just looked back at a typical flight to the fort. Probably more relevant than battery info, the flight was just under 9 mins which included a couple of mins flying around the fort. Just a steady 30kph/18mph on the way out and back.
Not yet, but it would be interesting. Needs a calm-ish day, but it’s less than a 15 minute round trip.
Theoretically, all three forts can be done in one flight … if you have a drone that manages about 21 minutes on a battery. Theoretically, my Mavic Pro can do this … but I’d need to check if any of my aging batteries can still manage that long.