BRIDGE OPENING: The Waldo-Hancock Bridge, which opened in 1931, was the first permanent bridge to cross the Penobscot River below Bangor. Prior to its opening, cars used a nearby ferry that operated upriver between Bucksport and Prospect.

BY THE NUMBERS: The bridge, which cost $846,000 to build, is 2,040 feet long. Its span is 135 feet above the Penobscot River and its two towers are 206 feet high.

REPLACEMENT BRIDGE: The replacement Penobscot Narrows Bridge, which opens next month, cost $85 million. It is 2,120 feet long and 571/2 feet wide, with towers that rise 440 feet high.