Old Oak

Old Oak is a castle in Game of Thrones. It is the seat of House Oakheart, a vassal house holding fealty to House Tyrell of Highgarden. The castle is located in north west of the Reach. It is north west of Highgarden on the Searoad near the border with the Westerlands.

In the books
In the Song of Ice and Fire novels Old Oak is the same.