The centre is based at the poet's former home in Cumbria

The centre at Grasmere will cost more than �3m, two-thirds of which came from the Heritage Lottery Fund.

The display will be housed in a new building at Dove Cottage, the former home of the poet in Town End.

More than 50,000 documents, works of art, and general memorabilia are held by the Wordsworth Trust.

It is an internationally important collection, which is currently kept in converted farm buildings, where it is difficult to look after the items properly and hard for visiting scholars to study them.

When the new building is completed it will allow students to examine the documents in comfort.

New letters

It will also enable much of the collection to be exhibited on the internet.

Usually about 75,000 people visit Dove Cottage, the Romantic poet's home, each year.

Since it was founded in 1891, the trust has developed a museum, archive, store, library and shop.

The new building will mean greatly-improved conditions for the long-term conservation and care of "Wordsworthiana".

As well as Friday's formal tipping of concrete into foundations, there will be a new presentation to the collection.

They include some letters from Wordsworth's sister-in-law which reveal how unhappy he was after his marriage to Mary Hutchinson in 1802.