Trilby Valley is a location in Breath of the Wild.
Breath of the Wild
Trilby Valley is a massive area filled with large rocks and hills, located just southwest of the Foothill Stable.
There are a number of enemy bases throughout the valley, with a variety of goodies. At the far southwest, there are numerous Bokoblin and Lizalfos, with a treasure chest inside that has a Silver Rupee. Another base can be found at a higher ledge to the east, and after defeating all the enemies, another chest with a Silver Rupee will appear. A third base can be found at the far northeast end of the valley, with either a Knight's Bow or Royal Bow in the chest.
Nearby Korok Seeds
Find the seed platform located up the hill toward Foothill Stable. Head from it to the target before time runs out to reveal the Korok. Shield surfing or paragliding makes this a breeze.