Plechý mountain (1,378 m) is the highest mountain of the Czech part of the Šumava mountains (Bohemian Forest). It lies 14 km west of the village Horní Planá and about 8 km south-west of the small village Nová Pec on the Czech-Austrian border.

A lot of places of interest can be found on its slopes and peak. One of them is the morainic Plešné Jezero (Plešné Lake). Above the lake, on a 211 m high rock face with a nice view of the lake, there is a 14.5 m high monument to the writer A. Stifter.

The rock face is a valuable geomorphological formation and is a part of the nature reserve Trojmezná Hora ("Three Landmarks Mountain"). The sea of stones with huge granite boulders lies near the moraine.
The trail of the Schwarzenberský Kanál (Schwarzenbergs' Canal) runs on the northern slope of the mountain. Interesting portals of the underground tunnel can be seen at the foot near the small village Jelení.

The red marked sierra trail leads from the small village Nové Údolí over the tops of Třístoličník mountain ("Three Stools Mount") and Trojmezná mountain ("Mount of Three Landmarks"). The trail is about 15 km long and takes about 5 hours. The yellow marked path leads from the peak of Plechý downhill to Plešné Jezero lake. Then the green marked path continues to Jelení. The green sign, which also runs from the lake, joins the blue one, which heads to Nová Pec.