The Red Bull Soapbox Race Sofia 2014, the first official soapbox car competition in Bulgaria, will take place on September 28.

The non-motorised racing event that challenges both experienced racers and amateurs alike to design and build outrageous, human-powered soapbox dream machines arrives in Bulgaria and will take place at Sofia's Cherni Vrah boulevard.

According to the rules, the soapbox cars cannot be wider than 2 metres and no longer than six metres, have to be at least 10 centimetres above the ground and no taller than 2.5 metres. It must not weigh more than 80 kilos and be powered only by gravity and imagination.

The participating teams are more than 60. There will be races for speed and prizes for most original and ingenious designs.

The races start at 11 am, along the steep part of Cherni Vrah boulevard above between the Hemus and Kempinski Hotel Zografski hotels.