Campaigners fighting to save their West Sussex hospital from closure are spending the next few days walking to London in protest.
Campaigners fear the hospital could become a "local general hospital"
It follows the announcement that two out of three accident and emergency departments will close in the county.
Supporters of St Richard's Hospital, in Chichester, set off on their 76-mile trek to the capital on Thursday.
A&E care at the Worthing and Southlands Hospital, and the Princess Royal, in Haywards Heath, are also in doubt.
West Sussex Primary Care Trust (PCT) announced plans to downgrade two out of the three hospitals on Wednesday.
Three options, under its Fit for the Future consultation, are being considered.
One of the proposals sees St Richard's Hospital losing its A&E department, maternity and complex surgery.
More than 136,000 people have signed a petition to save the hospital.
The petition will be delivered to Downing Street and the Department of Health at the end of the march to London next Tuesday.
It is the second time the protesters have taken their campaign to Westminster.