A HISTORIC tower was due to reopen on August 29 after it was rebuilt brick by brick to stop it falling in to the sea.
Clavell Tower was perched perilously close to the cliff edge at Kimmeridge Bay and was at risk of a watery grave thanks to coastal erosion.
An 18-month project, costing £898,000, has seen the monument on the World Heritage Jurassic Coast dismantled by specialist builders, with each of the 16,272 stones numbered and recorded.
The four-storey ruin was then rebuilt 82ft inland using as much original material as possible.
The Landmark Trust is reopening the tower today, ready for people to visit on Sunday and Monday.
Peter Pearce, director at the trust, said: "The tower's future is secure and it can now resume its role as sentinel on this stretch of coastline.
"Its familiar silhouette will continue to welcome the many thousands of people who visit and walk in Kimmeridge Bay each year."
The monument was built by the Rev John Richards Clavell in 1830 as an observatory and folly, with four storeys, including a basement, and a distinctive Tuscan colonnade.
It was used by coastguards but then fell into disuse, becoming derelict after it was gutted by fire in the 1930s.
It was the inspiration behind crime writer PD James' novel The Black Tower and the author backed the campaign to save the building, which is also known as the Tower of the Winds.
Writer Thomas Hardy often took his first love Eliza Nicholl to the Grade II-listed tower to court her and used an illustration of the landmark building opposite the title page in his Wessex Poems.
Adrian Tinniswood, of the Heritage Lottery Fund, said: "The Clavell Tower defines the local landscape and coastline."
The Landmark Trust, leaseholder of the tower, launched an appeal in 2004 to raise money to save it, later securing a £436,000 lottery grant.
It plans to let the tower out for holidays to make it self-financing.