Kostel Nanebevzetí Panny Marie in Blatná is a Roman Catholic church renowned for its historical significance and architectural beauty. Located in the town of Blatná within Jihočeský kraj, this monument stands as a testament to both religious devotion and artistic evolution from the 13th to the 19th century. Originally constructed as a Romanesque structure around 1290 by Bavory ze Strakonic, it was later replaced by a Gothic edifice between 1444 and 1515 under the patronage of Lva z Rožmitálu. The church is recognized as a cultural monument of the Czech Republic, reflecting its importance in both religious and architectural history.

The origins of Kostel Nanebevzetí Panny Marie trace back to the late 13th century when Bavory ze Strakonic built the initial Romanesque church around 1290. This early structure laid the foundation for what would become a significant Gothic transformation initiated by Lva z Rožmitálu in the mid-15th century. The transition from Romanesque to Gothic architecture marked a period of religious and artistic flourishing, influenced by broader European trends during the Gothic era. By 1444, under Jaroslav Lev z Rožmitálu, significant progress was made on the presbytery, completed with contributions from master Staněk and his sons. The church's nave was finished in 1515, culminating in its consecration that same year.

Architecturally, Kostel Nanebevzetí Panny Marie showcases a blend of Romanesque and Gothic elements. The oldest part of the church is a Romanesque sacristy, which retains features from the original structure. The presbytery, completed by 1444, exhibits intricate details such as a three-field net vault with star-shaped closures dating back to 1442. This section also includes a shallow late-Gothic oratory adorned with richly carved stone parapets for organ placement. The nave features four fields of shallow ribbed vaulting known as diamond vaults, characterized by four-pointed stars typical of South Bohemian architecture. These elements are supported by slender columns and flat pilasters with capitals along the outer walls, creating a harmonious blend of structural integrity and aesthetic appeal.

Throughout its history, Kostel Nanebevzetí Panny Marie has seen various changes in ownership and administration. Initially built by Bavory ze Strakonic, it was later overseen by Lva z Rožmitálu and his son Zdeňek. The church underwent significant modifications in the 18th century under Alžběta Serényiová, who commissioned baroque alterations to the chapel of St. Michael, now known as the Chapel of the Holy Sepulchre. These changes reflect the evolving tastes and religious influences over the centuries.

Key events in the church's history include its transformation from a Romanesque to a Gothic structure and subsequent stylistic modifications. A notable curiosity is the neo-Gothic bell tower constructed after a fire in the early 19th century, replacing an earlier baroque design by J. Spinetti. This tower not only serves as a striking architectural feature but also functions as an entrance to the cemetery surrounding the church.

Today, Kostel Nanebevzetí Panny Marie stands as a well-preserved example of Gothic architecture with Romanesque roots. Visitors can explore its rich history and intricate design elements, making it a worthwhile destination for those interested in cultural heritage and architectural evolution. The church's status as a protected cultural monument underscores its significance and invites exploration by both locals and tourists alike.

Kostel Nanebevzetí Panny Marie is more than just a historical site; it is a living testament to the artistic and religious fervor of past centuries. Its blend of Romanesque and Gothic styles offers a unique glimpse into the architectural transitions that have shaped its form over time. Visitors are encouraged to experience this remarkable monument, which continues to inspire awe with its enduring beauty and historical depth.