"Treasure your treasures" - that's the message from Lloyd Grossman, who is urging people to visit the cultural heritage on their doorstep as part of this year's Heritage Open Days event.

Grossman, who is patron of the festival, is joining forces with organises to make history matter with the UK's biggest annual grassroots celebration of church towers, cathedrals, historical venues, hidden places and secret gardens.

The event runs from Thursday, September 8 to Sunday, September 11 with more than 45,000 people expected to give up their time, creativity and skills in a cavalcade of free walks, talks, tours, open houses, exhibitions, performances and demonstrations.

“Heritage Open Days and its army of volunteers play an important role in championing our wonderfully diverse local heritage," explains Grossman, "opening up doors and keeping access free for these very special four days every year.

"Don’t miss this once-a-year chance to be a tourist in your own town and treasure the treasures on your doorstep.”

A host of Dorset's very own treasures will be available to explore during the event.

Here are just some of the highlights.

To find out about other venues taking part in Heritage Open Days, and when events are taking place, including details of open hours and booking, visit heritageopendays.org.uk

1. Mapperton House, Mapperton, Beaminster

Tudor/Jacobean manor house with church and stables. Tours last approx 1 hour and includes rooms and items not usually seen.

2. Blandford Fashion Museum, Lime Tree House, The Plocks

Blandford Fashion Museum is located in a beautiful Georgian Townhouse built by the Bastard Brothers in 1760. Current Costume displays include “Retro” which portrays changes in fashion from the 1920s to the late 1970s. Examples include 1940s utility clothing, items reflecting the freedom of the 1960s and the mini and maxi of the 1970s.

3. St. Andrews Church, Millhams Road, Bournemouth

Come and visit the oldest Church in Bournemouth. Late Norman tower, 13th century chancel (restored 1875), nave and aisles rebuilt 1894-95 by W.H. Romaine-Walker. Inside there are a number of historic artefacts, including a Hanoverian royal arms on canvas, prayer boards, a clock installed in memory of Queen Victoria in 1904, beautiful stained glass windows, and a WWI memorial plaque.

4. Talbot Heath School, Bournemouth

Talbot Heath School will be opening one of its four WWII underground bunkers which used to accommodate the whole school community during bombing raids. The 100ft bunker has been refurbished as it was during the war. There will be the opportunity to see fascinating archive materials from the war years at the school.

5. Hardy’s Cottage, Higher Bockhampton, Dorchester

The writer Thomas Hardy was born and grew up in this cottage, and wrote his early novels Under the Greenwood Tree and Far from the Madding Crowd here. Visitors can enjoy its homely atmosphere and savour a taste of the world Hardy captured in his novels and poetry.

6. The Guildhall, Bridge Street, Lyme Regis

The Guildhall can be dated to the sixteenth century. The main chamber, however, with its curved ceiling and extensive panelling was refurbished in 1887 by the same architect who built the Philpot Museum.

7. Upton House guided tours, Upton Country Park, Upton, Poole

Built in 1818 Upton House forms the focal point of the estate and has long been a jewel in Poole’s crown, with the House and grounds being bequeathed to the people of Poole in the 1950s. An insight into the history of the house, allowing you to discover facts about the Spurrier, Tichborne and Lewellin families and their time in residence at Upton House.

8. Sherborne Steam & Waterwheel Centre, Oborne Rd, Sherborne

During the day the waterwheel will be running and the large Hindley steam engine will also be running, under steam. There is a collection of stationary engines and vintage cycles to enjoy.

9. Clavell Tower, Kimmeridge Bay, Wareham

This four storey, circular tower stands high on the cliff above Kimmeridge Bay overlooking one of the most striking bays on the Dorset coast. Here is the Jurassic Coast, England's first natural World Heritage Site, and the South West Coastal Path runs past the door. Built in 1830, Clavell Tower's location has captivated many including writers like Hardy and P. D. James.

10. Lulworth Castle & Park, East Lulworth, Wareham

Walk in the footsteps of Kings and Queens as you explore the 17th Century Castle. Discover the stunning landscapes, beautiful 18th Century Roman Catholic Chapel and unrivalled views from the Castle tower.

11. Tudor House, Trinity Street, Weymouth

A merchant house dating from 1600 containing 17th century artifacts. A guided tour of approximately 45 minutes. Donations gratefully received.

12. The Priest’s House Museum & Garden, High Street, Wimborne

Discover the museum's stunning Roman wall paintings, the fascinating childhood gallery and a unique Victorian Valentine card collection as the museum tells the story of East Dorset. Explore period rooms from a 17th century hall to the working Victorian kitchen, finding out how life and work has changed in this historic townhouse.