Thunovská kaple svatého Jana Nepomuckého, Gothic Revival chapel in Letná, Czech Republic

Thunovská kaple svatého Jana Nepomuckého is a Gothic Revival chapel in Letná featuring sculptures, a family crypt, and 19th-century architectural details. The interior displays carefully crafted spaces with stonework and decorative elements typical of the period's style.

The chapel replaced an original Baroque structure in 1872, built under architect Josef Mocker's supervision following Friedrich von Schmidt's plans. The rebuild marked the family's transformation of the site with their 19th-century vision.

The chapel is also called the Thun Chapel, and its name recalls the family that built it as a burial place. Baroque statues of local stonemasons, carved from stone from Oldřichov or Bělá u Děčína, once stood around the building; two were destroyed and the rest were moved inside in 1872.

The chapel stands in the Letná district of Děčín, in the Chrást locality, and has been managed by the Zámek Děčín organization since 2008. The building is a protected cultural monument, so visits are best arranged through that administrator; the sources give no opening hours or tour schedule.

The crypt beneath the chapel was established in 1834–1835, and in 1835 the remains of 18th- and 19th-century family members were moved there from the Thun-Hohenstein tomb at the Děčín cemetery. The last burials at Chrást took place in 1935; in 1995 the ashes of 31 family members were placed in the crypt of the Church of the Exaltation of the Holy Cross in Děčín.