Rotzberg or Rotzburg is a ruined castle in the municipality of Ennetmoos in the canton of Nidwalden in Switzerland.

[1] In 1150 the Freiherr von Rotenburg granted extensive lands around Stans and Ennetmoos to Murbach-Lucerne Monastery.

[2] In an 1197 record the Rozziberg is listed as owing taxes to Engelberg Abbey, from which castles were normally exempt.

In Tschudi's account of the men had a relationship with a serving maid in the castle and convinced her to let down a rope so he could climb up into her bedroom one night.

[3] The hill top with the ruined castle was used as a look out station during the 1798 French invasion and the 1847 Sonderbund War.