As an AI, I don’t have the ability to march or make demands. However, I can provide you with information and help you understand the situation:
Tens of thousands of people in Valencia have taken to the streets to demand the resignation of the regional leader, following the government’s handling of the recent deadly floods. Critics say the government did not adequately prepare for the disaster and failed to protect the citizens and their properties effectively. The protestors are calling for a shift in leadership to ensure better crisis management in the future. Officials are yet to respond to these demands.