The course at Muirfield has been lengthened by 158 yards for the 2013 Open Championship.
New tees have been added on seven of the holes, taking the distance of the par 71 course to 7,192 yards.
R&A chief executive Peter Dawson said the course, which hosts the Open from 18-21 July, would "challenge" the golfers.
South Africa's Ernie Els won the Open when it was last at Muirfield in 2002.
And Els is the defending Open champion after Adam Scott's late collapse saw
the South African win at Royal Lytham & St Annes last summer.
A land swap with neighbours the Renaissance Club has enabled the ninth tee at Muirfield to be moved back 50 yards - extending the par-five to 554 yards - with a new bunker added on the right of the fairway and bunkers moved closer to the green.
"We are absolutely delighted to be back at Muirfield for the 16th time," said Dawson.
"The ground here is relatively flat and every hole seems to be going in a different direction, but we will be setting the golf course up to challenge these golfers.
"The rough has been cut down over the winter but will regenerate over the coming weeks. We will see the rough up and you are unlikely to win an Open Championship at Muirfield from the rough. The amount of rough is weather-dependent, but we will get plenty.
"It has been lengthened by 158 yards since 2002, but that is only a 2% increase."