Concrete piles are being sunk 17 metres deep on Weymouth Pier in preparation for the building of a £3.5 million observation tower which will soar 53 metres high and give visitors a bird’s eye view of Olympic sailing events.

The piles will provide a circular watertight curtain for the main excavation works.

The observation pod which will revolve to give a 360 degree view of the dramatic Jurassic coast and town is being built by German firm Huss at Bremen and will be shipped to England in sections.

It can carry 70 passengers at a time, revolving around a 2.5 metre diameter central steel column. The entire tower will weigh 130 metric tonnes.

In January a huge mechanical digger will begin the seven-metre deep hole for the Tower’s foundations.

Weymouth & Portland Borough Council has agreed to grant a five-year lease to the Tower’s builders, Merlin Entertainments Group.

Merlin, which also operates the London Eye and Weymouth Sea Life Centre, says the tower could attract up to 50,000 visitors a year.