The Church of Panagia Kapnikarea is a Byzantine-era church in the heart of Athens, Greece. The church's name is derived from the Greek word "kapnikon," which means "smoke shop" or "tobacco shop," as the area surrounding the church was once known for its tobacco merchants.

The church's architecture is a unique blend of Byzantine and Romanesque styles, resulting from the church's construction over several centuries. The oldest parts of the church date back to the 11th century and the church was expanded and renovated over the years to accommodate the growing congregation.

One of the unique elements of the church's architecture is its dome, made of brick and one of the oldest surviving brick domes in Greece. The dome is supported by four columns carved from marble and decorated with intricate designs.

Another notable feature of the church is the part dedicated to St. Barbara. St. Barbara is a Christian saint martyred in the 3rd century for her faith. According to legend, she was imprisoned in a tower by her pagan father but escaped by creating a third window in the building, which is said to represent the Holy Trinity. St. Barbara is the patron saint of architects, builders, and stonemasons, and her image is often depicted in Byzantine art.

The church area dedicated to St. Barbara contains several unique architectural elements, including a carved marble screen and a pulpit shaped like a ship. The ship-shaped pulpit is a nod to the maritime history of Greece and a symbol of the church's mission to guide its congregation through the rough waters of life.

Overall, the Church of Panagia Kapnikarea is a unique and historically significant building that reflects the blending of different architectural styles over the centuries. The church's dedication to St. Barbara is a testament to the importance of faith and perseverance in the face of adversity, and the church's unique features serve as a reminder of the rich cultural heritage of Greece.