Early sleeve design

On Monday, Lego is celebrating the 50th anniversary of the day it filed its first patent for the iconic plastic brick. Since the beginning, Lego sets have been themed, and the very first theme was space. Not long afterward, Lego added castle and pirate themes. One of the first major elements of the "System of Play" was the Lego Town Plan. To celebrate the 50th anniversary, the company is releasing a new, updated commemorative Town Plan this year. While updated, it includes '50s-era elements like a gas station, car wash, and garage, plus a movie theater and, of course, a town hall.

The original Town Plan box from 1955 featured Lego founder Ole Kirk Christiansen's grandson Kjeld Kirk Kristiansen as a boy. The 2008 Town Plan box once again features him, this time as a grown man.

Over the years, the Lego brick has become one of the most recognized toys in the world, and millions upon millions of people have spent countless hours playing with the bricks and the sets they're part of. But Lego's first supplementary sets came out in 1956, two years prior to the company filing its patent for the now-famous plastic brick. In 1956, the company exported its first products to Germany.

This year, Lego is also celebrating the 30th anniversary of the Minifigure, small figures of people included in many Lego sets today.