Signal Festival is Prague's festival of light, which takes place every four days in October. It has been held since 2013 and during its existence the festival has become one of the largest cultural events in the Czech Republic. The festival combines visually interesting works with high-quality installations.

The festival was founded by producer Martin Pošta, curator Jan Rolník and artist Amar Mulabegovič from the art group The Macula. After the success of video mapping on the 600th anniversary of the Old Town Astronomical Clock, which was carried out by group The Macula with Martin Pošta in 2010, the idea of a wider presentation of the lighting arts in the Czech Republic was created through the festival. Preparations of the first year took a total of 3 years. The organizers succeeded in bringing big names from all over the world to Prague and, with the support of the City of Prague, several Prague districts and other partners, established the tradition of the Light Festival.