Kleinbahnwiki is a German-language information resource dedicated to H0fine narrow-gauge and light railway modelling within FREMO. Its pages introduce the history and context of real Kleinbahnen—non-state railways planned, built, and operated under the Prussian Kleinbahn Act or similar regional legislation—and connect these prototypes with practical model railway projects. The site brings together construction blogs, detailed build reports, guidance on making modules, tracks, switches, signals, landscapes, and buildings, and tips for model builders.

It also covers rolling stock, road vehicles, railway technology such as DCC and boosters, and operating practices including timetables, freight documents, and wagon cards. Readers can explore prototype photographs, module displays, downloadable material, links, literature, FAQs, and reports from FREMO meetings. Project updates and photo collections document layouts, models, and railway locations.

The wiki invites contributions, provides information for editors, and offers contact details and file-upload options. With hundreds of pages and a substantial image collection, Kleinbahnwiki serves as a shared reference and archive for enthusiasts interested in researching, building, and operating miniature Kleinbahnen