Item 15575 - Open air theater, Riverton Park, Portland, 1902 Item 15575 - Open air theater, Riverton Park, Portland, 1902 Contributed by Maine Historical Society Item 15575 Zoom 4133px x 3467px - 13.8"w x 11.6"h @ 300dpi | Need a larger size? *Credit line must read: Collections of Maine Historical Society Image Info The open air theater at Riverton Park in Portland, part of a recreation complex on the trolley line. Show Details