Campaigners are protesting against what they say are "life-threatening cuts" at the QE2 in Welwyn Garden City...
The Welwyn and Hatfield "Keep the NHS Public Campaign" will be outside the hospital between midday and 4pm.
They're unhappy at a number of major services moving to the Lister Hospital in Stevenage, ahead of the rebuilding of the QE2.
Organiser Barry Cross told JACK fm he doesn't believe the plans are beneficial: "We don't think the Lister Hospital will be able to cope - we've got more people coming into the area and more people being born.
We need two hospitals NOT one-and-a-quarter, as we will have when this goes ahead.
There are alot of people who support the QE2 services staying as they are, but they won't realise the changes being made until they need to use services."
Speaking recently, the chief executive of East and North Hertfordshire NHS Trust, Nick Carver, said: "We are delighted to be supporting NHS Hertfordshire in its plans to create the New QEII Hospital.
We are now carrying out initial preparatory works to allow us to move some of the services located in outlying buildings in to the main hospital, thus ensuring that patients continue to receive high quality services in this interim phase prior to the New QEII being built by 2014.
Over the coming days and weeks, we'll be working to make sure that patients and their carers who have been used to attending our services in their existing locations are made are of their new locations in the main QEII tower block.
Improved signage is also being put in place to support these changes."