Narrow gauge railways in Germany

We don't know which railway these photos were taken on. Can you help us classify them?

• Ahr Valley (2 images)
• Brohltalbahn (1 images)
• Dresden Park Railway (1 images)
• East Germany (17 images)
• Fightelbahn
• Grubenbahn Museum Fortuna.
• Harzer Schmalspurbahnen (29 images)
• Loessnitzgrundbahn
• Muskauer Waldeisenbahn
• Plettenburg (7 images)
• Pressnitzalbahn.
• Steelworks
• Stumpfwaldbahn Ramsen (8 images)
• Wuppertal Monorail (4 images)