Health chiefs in Powys have voted to cut services at four community hospitals, but objectors claim this will only lead to their closure.
Llanidloes hospital will lose 16 beds under the LHB's plans
Powys Local Health Board intends to axe beds, shut a maternity unit and cut other services at Llanidloes, Knighton, Bronllys, near Brecon and Builth Wells.
Llanidloes councillor Gareth Morgan said it was the "blackest day" in the history of the town.
The health board said public consultation would begin next year.
About 100 campaigners lobbied health chiefs outside the meeting in Bronllys on Wednesday, with about 30 having travelled from Llanidloes by bus.
The health board said it was facing a £3.5m deficit and had to make changes.
At Llanidloes, the board voted to cut 16 beds, close an X-ray unit, a birthing centre and outpatient services.
Bronllys, near Brecon, and Knighton will lose GP beds and maternity services, while 12 GP beds, outpatient and X-ray services will be cut at Builth Wells.
Campaigners were critical, and Llanidloes county councillor Gareth Morgan said the hospital and its staff were the most "precious commodity" the town had.
"This is the blackest day in the town's history, but we will not give up fighting for our hospital - people in Llani are made of sterner stuff," he said.
Before Wednesday's meeting, Andy Williams, chief executive of Powys LHB, said he understood people's attachment to their hospital.
He added: "We must not allow ourselves to measure the effectiveness of health services by the number of hospital beds and by bricks and mortar.
"Some of our current buildings are outdated and we believe that the people of Powys deserve better."