Access to Musgrove Park Hospital from the Wellington Road will be closed over the Bank Holiday Weekend.
NHS Somerset Foundation Trust, which manages the hospital, announced the closure on Monday, May 22.
They said the entrance from Wellington Road would be closed from 6am on Saturday ,May 27, until 9pm on Monday, May 29.
The Trust asked those travelling to the hospital to use the Parkfield Drive Entrance while the closure was in place.
The temporary closure has been instituted as part of development to the surgical centre at the hospital.
The diversionary route will mean visitors travelling from Wellington will have to drive around an extra mile to two miles depending on if they arrive via Galmington or by turning right past Tesco onto Parkfield Drive, risking getting caught up in town centre traffic.