which countries were participating in it?
San Marino, Azerbaijan, Germany and Spain, to name a few.
Eurovision Song Contest 2008
On 21 December 2007, the EBU confirmed that 43 countries would be present in Belgrade. San Marino, as well as the newest EBU member, Azerbaijan, made its debut at the 2008 contest. Austria did not compete; its broadcaster, ORF, said "we've already seen in 2007 that it's not the quality of the song, but the country of origin that determines the decision." Italy, which had not competed since 1997, and which would have been an automatic finalist, was again absent. Slovakia was absent due to budget problems.

The following countries competed in two semi-finals which were broadcast live on Tuesday 20 May and Thursday 22 May 2008. In addition to this, automatic finalists Germany and Spain exercised voting rights at the first semi-final. France, the United Kingdom and Serbia exercised voting rights at the second semi-final. Spain and France each broadcast only the semi-final in which they participated; Germany, Serbia and the UK screened both semi-finals (with Germany broadcasting on a delay)
where is belgrade located? At the confluence of the Sava and Danube rivers and the crossroads of the Pannonian Plain and the Balkan Peninsula. what happened during the wwi in this city? Most of the Balkan offensives occurred near Belgrade - Austro-Hungarian monitors shelled Belgrade on 29 July 1914. what can you tell about this place's culture? According to BBC, Belgrade is one of five most creative cities in the world. are there any contest held here? Eurovision Song Contest 2008 was held here.
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Eurovision Song Contest 2008 [SEP] Participating countries
On 21 December 2007, the EBU confirmed that 43 countries would be present in Belgrade. San Marino, as well as the newest EBU member, Azerbaijan, made its debut at the 2008 contest. Austria did not compete; its broadcaster, ORF, said "we've already seen in 2007 that it's not the quality of the song, but the country of origin that determines the decision." Italy, which had not competed since 1997, and which would have been an automatic finalist, was again absent. Slovakia was absent due to budget problems. The following countries competed in two semi-finals which were broadcast live on Tuesday 20 May and Thursday 22 May 2008.