1. Russian Architecture vs. Gaudi Building

2. Saint Basil's Cathedral
The St. Basil's Cathedral was commissioned by Ivan the Terrible between 1555 and Its construction was to commemorate the capture of the Khanate of Kazan, which happened on the feast day of the Intercession of the Virgin.
The building's design, shaped as a flame of a bonfire rising into the sky, has no analogues in Russian architecture: "It is like no other Russian building. Nothing similar can be found in the entire millennium of Byzantine tradition from the fifth to fifteenth century... a strangeness that astonishes by its unexpectedness, complexity and dazzling interleaving of the manifold details of its design."[The cathedral foreshadowed the climax of Russian national architecture in the 17th century but has never been reproduced directly.

3. Barcelona Gaudi Building
When Gaudi first started out, his works were primarily Gothic in nature and had a traditional Spanish flare to them. After a few years, he went on to develop his own style, which was when his most popular works were created. The nature he had studied so much as a child was soon to be incorporated into his works and he showed amazing portrayals of water and organic shapes in his architectural designs. Later his work became known by the name Art Nouveau Architecture, and was actually a precursor to today’s modern architecture (known as 'modernisme').

4. How are they similar and How are they different?
Barcelona Gaudi Building
Saint Basil's Cathedral