The Church of the Holy Trinity in Krásný Les is a baroque-style sacred building located in Jindřichovice pod Smrkem, within the Frýdlantské Vrchy region in northern Czech Republic. Originally constructed as a chapel, it expanded into a church by 1670 and underwent significant architectural transformations throughout the 18th century. The addition of a presbytery in 1717, along with further modifications around 1775 and at the turn of the 19th century, enhanced its baroque style. Recognized as a cultural monument of the Czech Republic, this church is notable for its intricate architecture featuring a single nave with an extended presbytery, a polygonal tower, and detailed interior decorations.

The origins of the Church of the Holy Trinity trace back to a chapel expanded into a larger structure by 1670. This expansion marked the beginning of significant architectural development, continuing with the addition of a presbytery in 1717. Further modifications occurred around 1775 and at the turn of the 19th century, enhancing its baroque style. These changes reflect the broader historical context of Bohemia during this period, which was part of the Holy Roman Empire under Habsburg rule. The region experienced significant religious and cultural shifts during the Reformation and Counter-Reformation periods, influencing architectural styles such as baroque.

Architecturally, the church is a quintessential example of baroque design. It features a single oblong nave complemented by an extended presbytery with convex-concave walls. On its northern side sits an oblong sacristy, while a rectangular vestibule on the southern side serves as the entrance to the church. The polygonal tower, adorned with lisenes and windows in oval and rectangular shapes, is topped with a bulbous dome. Boasting segmental arches, the exterior of the building is further defined by two bands of lisenes and segmentally arched windows. Inside, both the nave and presbytery are characterized by flat ceilings enhanced with stucco decorations. The sacristy features a net vault, while the space beneath the tower has a truss ceiling. A notable feature within the church is its choir screen, crafted in classical style in 1802.

The interior of the Church of the Holy Trinity houses several significant artifacts and furnishings. It contains one main altar and two side altars from the 19th century, alongside a pulpit dating back to the turn of the 18th and 19th centuries. A baroque baptismal font from the latter half of the 17th century is complemented by a rococo base and cylindrical pedestal. The church also features paintings of Saint Philomena and Saint Louise, both dated to 1856. The original organ, built in 1709 by Johann Jakub Josef Richter, underwent several modifications over time, including significant reworking by Josef Müller.

Surrounding the church is a cemetery featuring four neoclassical gravestones from the early 19th century and another from 1835. Near the southern entrance stands a late baroque belfry with an oblong base and pyramidal top, adorned with pilasters, recessed fields, and an oblong portal, capped by a shield featuring segmental elements.

Today, the Church of the Holy Trinity remains a significant cultural monument in Krásný Les. Its rich history and architectural beauty make it a worthwhile visit for those interested in baroque architecture and Czech cultural heritage. Visitors can explore its intricate design and appreciate the historical artifacts within, gaining insight into the religious and cultural transformations that have shaped this region over centuries.