River Raid was first released on the Atari 2600 (VCS) system in 1982. A year later or so, it was available on the Commodore 64.
River Raid has got to be the reference in terms of vertical scrolling shooter games, and it's not just because it was the first one to be of the scrolling kind. The game play is quite simple (probably due to the hardware limitations of the Atari) but it's pretty addicting.
River Raid starts off easy and as you reach further and further bridges, the level of difficulty kinda rises exponentially. As many, I have no idea how many bridges you need to fly over to reach the end of the game, assuming there's an end to it. You've got all kinds of foes to deal with, in particular, helicopters, battleships, balloons, jets, tanks, and probably many others I haven't seen. The jet that you fly actually consumes fuel, so you need to fly over the fuel stations in order to avoid running out.
The layout is supposed to be generated at random every time you play, so it was kind of ground breaking at the time. The memory limitations of the Atari had probably something to do with that.
The game was designed by Carol Shaw at Activision, a woman among men at Activision, back in the early days.