Dub Král, Solitary oak tree in Grygov, Czech Republic.

Dub Král is a protected oak at the edge of the Království nature reserve near Grygov, growing right beside the railway track. Its trunk measured 560 cm in girth in 2006 and the tree stands 31 m tall, with a crown that begins at about half its height because lower skeletal branches were removed.

The oak was declared a protected monument on 27 January 1973. In 2003 a circular wooden platform was installed at its base, but the removal of strong skeletal branches shifted the tree's centre of gravity; its condition, rated very good in 1972 and 1997, was described as heavily damaged by 2006. The platform and a wooden access walkway were repaired in 2006.

The oak's name comes from a legend about King Wenceslas III, who in 1306 fell asleep under an oak while hunting in the royal forest and dreamed of fairies, a fawn and a wolf. After waking he gave the forest to Olomouc and ordered that the tree never be felled; when the original died, a new oak was planted in its place.

The tree sits on open, accessible ground, making it easy to reach and visible from a distance. Visitors should know that the site is exposed to the elements, so proper clothing and weather protection are advisable.

The tree appeared in the eighth episode of Czech Television's series Paměť stromů, titled Stromy královské. Its crown now begins at about half its height because strong skeletal branches were removed in 2003, shifting the tree's centre of gravity.