The latest LEGO Architecture sets 21010 Robie House
The original (non-LEGO) Robie House was designed by Frank Lloyd Wright and built in 1910, 25 years before Fallingwater.
The Brandenburg Gate in Berlin was built in Berlin between 1788 and 1791. The LEGO version has 363 pieces, including quite a nice batch of sand-green cheese slopes, and goes for $34.99.
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