Building Sets are the plain DUPLO brick sets, buckets and boxes of bricks without a story. DUPLO started in 1969, and the name comes from the Latin word for double, because each brick is twice as long, wide and high as a LEGO brick. The studs are made to fit, so DUPLO and LEGO bricks lock together and a builder can move from one to the other. For years the plastic bucket was the usual way to sell them, from the 1980s through the early 2000s, often shaped or printed as an animal, a farm or a circus, and some came as anniversary editions. Later sets switched to cardboard brick boxes with ideas for what to build on the side.
1973 LEGO Sets
1973 marked major structural and product milestones for LEGO. The company ended its U.S. licensing agreement with Samsonite and established LEGO Systems, Inc. in Brookfield, Connecticut, giving LEGO direct control over its American distribution. DUPLO was formally branded as a standalone preschool line, expanding on the larger bricks first introduced in 1969. Early Town sets began to appear with simple, posable figures—precursors to the modern minifigure—bringing more life and movement to everyday scenes. LEGO’s catalog continued to grow rapidly, reinforcing its position as a leading global toy brand.