Seventeen thousand students in Spain's Comunidad Valenciana region had been preparing for an exam that would grant only 500 of them a job as a nursing assistant in the region’s hospitals.

One can only begin to imagine the despair some of the candidates must have felt when they were physically unable to reach the exam room despite having the set off on time on Sunday morning.

The reason for the frustrating delay was none other than a half marathon taking place in the coastal city at the same time as the public service entry exams were being carried out at Valencia University.

The sporting event held up traffic around Valencia and blocked access to some of the roads leading to the campus.

"Police officers have helped us out but there was total gridlock on the roads and we’ve simply been unable to arrive on time," one of the candidates told Spanish National Television.

"It's not fair, we’ve been waiting for this opportunity for so long."

Spain’s general trade union CC OO has criticized Valencia's Town Hall and Health Ministry for not foreseeing the clash between both events.

The syndicate had warned the region’s health ministry a week before in a letter in which they insisted on “alternative routes to avoid any possible problems".

They've been too strict with the time limit,” Yolanda Gil, spokesperson for Spain's Nursing Trade Union told Spanish radio station Cadena Ser.

"There were people crying because they had been preparing for two years and they’ve not even been able to sit the exam."

A total of 17,615 candidates sat the public service entrance exam in the region’s thee main cities: Castellón, Alicante and Valencia.