Byzantine Architecture

[The Great Uniter]

Early Byzantine architecture influenced the Romanesque one, this is the reason to see similarities.

They are still pretty much the same for me: Smooth colons, small arches, curved or triangular dome and focus on ecclesiastical buildings. I am no expert at architecture. They are both Roman architectural designs.

[PAGANE]

The Church of Saint George is an Early Christian red brick rotunda that is considered the oldest building in Sofia, the capital of Bulgaria. It is situated behind the Sheraton Hotel, amid remains of the ancient town of Serdica.

[MinervaItalica]

Cattolica di Stilo, Calabria (Italy)

[Aspirin]

They are still pretty much the same for me: Smooth colons, small arches, curved or triangular dome and focus on ecclesiastical buildings. I am no expert at architecture. They are both Roman architectural designs.

Yes, you are right, but early Byzantine architecture clearly had a big impact on Western European architecture. The most famous example is Aachen Chapel in Northern Germany builded by Charlemagne.