In the month that it’s been open—yes, it’s already been just about a month—the Second Avenue subway line has already become an indispensable part of many New Yorkers’ lives, providing an easier connection from the Upper East Side to the rest of Manhattan. But it’s unlikely that people will forget what it took to get there: a century of planning, a few fits and starts, and a race to the finish line.

For those who are curious about how the line went from pipe dream to reality, the New York Transit Museum has you covered: the institution’s Downtown Brooklyn location is now hosting “Next Stop: Second Avenue Subway,” an exhibit looking at the (very, very) long history of the Second Avenue line.

The museum dug into its own collection to tell the Second Avenue Subway’s story, from its earliest days (including the construction and expansion of the elevated line that once ran along the thoroughfare) to the eventual completion of the line at the beginning of the year. There’s a treasure trove of old maps, subway tiles, and vintage photos—including one of NYC legislators celebrating the line’s groundbreaking in 1972, if you need a laugh.