Blatná, Natural monument and protected area in Blatná, Czech Republic.

Blatná is a 43.77-hectare natural monument on the south-western edge of the town of Blatná, in the Strakonice district, at 432–452 m above sea level. It consists mainly of the Zámecká obora park, an English-style landscape park with old solitary broadleaved trees, the Naděje pond and a brook, and the Lomnice river along its northern border.

The English-style castle park was created from a former hunting preserve at the wish of František Hildprandt between 1850 and 1856; an artificial hill with rocks and caves had already been built in its south-western part in 1810. The South Bohemian Regional Authority declared the natural monument with effect from 2 January 2014 to protect the population of the brown click beetle Osmoderma eremita.

The park began as a hunting preserve of the Hildprandt family and was landscaped in the English style by František Hildprandt between 1850 and 1856. Fallow deer have been kept here since the mid-19th century and now roam the whole area, which townspeople and castle visitors use for short walks.

The monument lies on the south-western edge of Blatná, in the flat floodplain of the Lomnice, which runs along its northern border. A ditch branches off near the Řečický rybník, feeds the Naděje pond and joins the river inside the grounds. The terrain is level, between 432 and 452 metres.

The beetle Osmoderma eremita lives only in hollows of old solitary broadleaved trees, which landscaping kept in the park. The Blatná population was small when the monument was declared, but the number of suitable hollows gave it room to grow.