Spaniards have been turning out in force today to cast a vote for democracy and end almost 40 years of dictatorial rule.
The majority of the 25 million Spaniards eligible to vote are expected to endorse a new constitution in the historic referendum.
It would strip the monarchy of much of its current powers, many of which were handed down by the late dictator General Franco, who died in 1975.
King Juan Carlos and Queen Sofia support the move and were among the first to cast their vote in a village school near Madrid.
Prime Minister Adolfo Suarez, leader of the Union of the Democratic Centre UCD, a moderate centre-right coalition, has drafted the new democratic constitution.
It could eventually put him out of a job if new elections are held as a result.
Last June saw Spain’s first elections to the Cortes (parliament) since 1936 and in which Mr Suarez won 34% of the votes.
Tens of thousands of children, not able to vote, still had reason to celebrate as they have had the day off with schools converted into polling stations.
But there was still an air of tension in the country after a recent spell of murders and bombings, attributed to Basque separatists in the northern Basque region.
Riot police and soldiers are on high alert, guarding polling stations and communication centres.
The fear of violence is reported to have led an estimated 250,000 Spaniards to cast a postal vote.
Courtesy BBC News
The new constitution was overwhelmingly supported by voters with newspapers the following morning congratulating Spaniards with headlines such as “Good morning, democracy”.
It established Spain as a parliamentary monarchy.
Spain continued to shake off the Franco years which had left the country alienated internationally.
It invested heavily to win European support and became a member of the EC, now the EU, in 1986.
This required it to open its economy, modernise its industrial base and improve infrastructure.
The country has been dogged by separatist violence in a long-running campaign by the Basque Fatherland and Liberty (ETA), founded in 1959 and dedicated to promoting Basque independence.