"Wonderland by Night" (German title "") is a popular song by Bert Kaempfert that was a Billboard number one hit for three weeks, starting 9 January 1961. Written by Klaus Günter Neumann with English lyrics by Lincoln Chase, it was recorded in July 1959 and became Bert Kaempfert's first hit with his orchestra. The song featured Charly Tabor on trumpet. "Wonderland by Night" also crossed over to the R&B chart where it peaked at number five.
A German-language numbers station (G10) was operated by one of Polish intelligence agencies and was active until the late 1970s, which used Kaempfert's version of the song, and its B-side, "Dreaming the Blues", both repeated twice in chronological order as its interval signal, followed by the average format of a numbers station, this interval signal leading it to be commonly nicknamed by Shortwave radio enthusiasts after Kaempfert. It was later replaced by G11 (nicknamed "Strich"), which was most recently active from 2007 to 2014.