At the base of the Triborough bridge (where the pedestrian walkway starts in Astoria) there is a wonderful, vintage and cast metal map of Randalls Island:

Note the red button on the right-hand side that indicates where you are.

Note how Wards Island was not ‘open’ to the public (greyed out) and had a dock on the east river. There is also a more significant water/marsh/wetland separating the two islands at the time – although admittedly they were physically joined by infill.

The presence of the Wards Island Bridge (at 103rd Street) on this map indicates it dates from after May 18, 1951: https://en.wikipedia.org/wiki/Wards_Island_Bridge

The baseball fields (one of which seems to have bleachers) are indicated as 1/4 circle indents.

Downing Stadium – now Icahn – had a more Greco-Roman, half oval set of stands at the time.

Today, the printed map – enamel on fiberglass – looks much different:

With public space on Wards Island, welcoming the public.

Seen on FDB