A hospital that served Kent and Sussex since the 1930s is closing as the new £230m Tunbridge Wells Hospital built at Pembury opens its doors.
The new A&E opened at 02:00 BST at the same time as the old A&E at the Kent & Sussex Hospital closed.
Glenn Douglas, Maidstone and Tunbridge Wells NHS chief executive, put up closure signs at the hospital at 13:30 BST, when the whole site shut.
The new hospital has all single en-suite bedrooms, and holds 512 beds.
It has been built on the site of the old Pembury Hospital that was also run by the trust.
Mr Douglas said: "It's certainly the biggest move I've ever done.
"Some years ago I was part of the move from the old All Saints Hospital in Chatham into Medway Maritime Hospital so it's not a totally new experience for me - but this is a much much bigger move.
"It's been a massive logistical exercise but in fairness, with all the efforts of the staff, we've managed to iron out all the eventualities."
And before the move, he said: "Obviously there's always the unknown unknowns, but we feel we're prepared for anything that can happen."
Building work on the Pembury Hospital started more than three years ago, and planning for the move started six months ago.
The first patients were welcomed to the new hospital in January with the second phase of the move taking place this month. This week, 200 patients were moved to the hospital in a specially-adapted coach.
On Tuesday, chief nurse Flo Panel-Coates said: "Some of the staff came in at six o' clock this morning to get their patients ready to make sure that they were washed and dressed and prepared and supported in preparation for the move and I'm so proud of them."
The A&E handover took place in the early hours because it was the quietest time of day. The two emergency departments opened and closed simultaneously.
The old Kent & Sussex Hospital site has been earmarked for housing and will be sold to a developer, with the funds used to buy medical equipment for the new hospital, the NHS trust said. The sale is expected to raise millions.
The old Pembury Hospital - a former 19th Century workhouse that became a hospital in 1938 - has been completely demolished.
Hi-tech gadgets at the new hospital will see nurses using wireless communications to receive patient call alerts on cordless phones which they carry with them.
Nurses at base stations will also be able to check equipment monitoring patients in their rooms, again by using wireless technology.
An imaging scanner that has twice the magnetic power of that in the old Pembury Hospital has been installed on a specially-strengthened floor.
And a £200,000 pharmacy robot called Doris will be used. Doris - given a female name because she can multi-task - sorts and dispenses medicines and delivers them via a helter skelter pipe into ward trolleys.
Doris has 30,000 packs of medicine at her fingertips and can be repaired remotely by an engineer using a webcam.
The hospital has 12,000 wall-mounted dispensers for handwash gel, surgical gloves, plastic aprons and wet wipes.
And 380 Freeview flatscreen TVs have been installed in patient rooms throughout the hospital, paid for by a £340,000 donation from the League of Friends.
The hospital said the healing environment of a bright and airy room, a relaxing woodland view, privacy and the chance of a better night's sleep were all vital to a patient's recovery.