Should not be too difficult to finish. The missions are connected pretty well. As others said, GPS is tricky among buildings. On March 24, the Olympic park was closed (maybe temporary) so remember to check the availability before the start. One star off because of that stupid gross green border.
Estimated complete time: About 3 hr
MD 2019 Bristol ArrayQueue Completed all 24, starting with those at the north of the city and going towards the Clifton Suspension Bridge.
From that position, Brandon Hill and Clifton are VERY high up. If you are a wheelchair user, then these will be tough I'd imagine. VERY steep. Please be careful.
With that said, the views overlooking the bridge are beautiful, so well worth the climb.
Watch out for Rain in Paradise Park Morganza Four laps around the portal-dense dirt/cinder walking path in the park, a few portals require walking across the grass. Path is clean and intuitive -- you can generally guess where the next mission starts.
Corn Creek Ladybug Morganza I tried to do this but signal with AT&T kept coming and going. Fortunately I gave up on the first mission.
Jawor Lineusz Trasa ostatniej misji strasznie spaprana, zamiast jakoś sensownie pokierować po rynku i okolicy rzuca z kąta w kąt.
Hasło pierwsze z godnie z opisem czytelnie na Tablicy, drugie ( kończące ostatnią misję) do wygooglowania i wyczytania w Wikipedii.