The project was organised by the US Embassy in Bosnia and Herzegovina with the aim of encouraging young people in the country to say what kind of a country they wanted to live in in 20 years' time. Their messages will be put in a special metal container to be opened in two decades when they will be compared with the actual situation in the country.
Presenting the project at an event in Sarajevo, US Ambassador Maureen Cormack said that more than 20,000 young people took part in the project and that their main message was that they wanted to live in a country of peace, progress and unity.
Cormack was hopeful that in 2035, when the time capsule would be opened, the wishes of those young people would be a reality.
She added that 20 years after the Dayton Peace Agreement's coming into life it was time for those born after the 1992-95 war to start making key decisions in Bosnia and Herzegovina.
The Bosniak member of Bosnia and Herzegovina's three-member Presidency, Bakir Izetbegovic, said that there had been mistakes and political meandering in the past years, but that there also had been an undeniable desire for equality, freedom and democracy.
"With different people and a different approach, the Dayton Agreement and Bosnia and Herzegovina will be different and better," Izetbegovic said, adding that what would always remain the same was the need for mutual respect, patriotism and respect for the country's diversity.
In a video message shown at the event, US Secretary of State John Kerry wished its participants a society of true democratic values.
We want you to become a democratic, prosperous and successful society, Kerry said.
Congressman Mike Turner, chairman of the NATO Parliamentary Assembly who 20 years ago was the mayor of Dayton, was also in Sarajevo today.
Despite difficulties, progress in today's Bosnia and Herzegovina is evident even though a lot remains to be done, said Turner.