No entry, keep out, access to authorised personal only — there are plenty of places usually off limits. But if you're in the know you can go behind-the-scenes everywhere from a hi-tech car factory to the zoo. SIMON PARKIN looks at places where it pays to be nosy.

CLOCK TOWER

It looms over Norwich city centre, and finally seems to be regularly telling the right time — barring the odd cold weather stoppage — but the clock tower also offers unparalleled views. Join a tour of City Hall's stunning 1930's art deco styling and furnishings and there is the chance to climb the 166 steps to the top of the 206ft high tower. Children under eight years aren't allowed, suitable footwear must be worn and no one with a heart condition or similar should attempt the climb.

To find out about tours and prices contact the Tourist Information Centre on 01603 213999, www.norwich.gov.uk

WIND TURBINE

It's not exactly hidden – standing almost 100m tall in one of the flattest landscapes in the country sees to that – but it doesn't top most must-do lists either. However, as the only wind turbine in the world which the public can climb, using the world's highest spiral staircase, the Ecotech Centre at Swaffham offers a behind-the-scenes chance to see a turbine up close. The centre is open Mon-Fri 10am-4pm (they don't open at weekends until the summer). Wind turbine tours, up 305 steps, cost �6 (�5 cons), �4 children (ages 7+, minimum height 1.20m), �18 family. Pre-book on 01760 726100, www.ecotech.org.uk

TV STUDIO

We've all walked past the Forum studios, we've all watched or listened to the programmes, but have you ever wondered just what goes on in the BBC's Norwich outpost? Well the BBC offers a fantastic chance to gain access to the rarely seen world behind the TV and radio programmes on its behind-the-scenes tours. The events include a visit to the Look East TV studio and production gallery, a peek into the presenters' dressing-rooms, a wander through the Radio Norfolk studios while they are broadcasting, plus a look at the new purpose-built Open Studio that gives the chance to try a hands-on interactive studio experience. Tours last up to an hour and cost �6.15 (�5.75 cons), �5.15 children (aged 7-15 years). Pre-book on 0370 9011227, bbc.co.uk/showsandtours/tours/norwich.shtml

CATHEDRAL TOWER

St John's Cathedral is the second largest Catholic cathedral in the country. The sweeping views from the tower may be familiar, as Anglia TV have a camera on top that provides images during their nightly news programme. Guided tours run on Saturdays at 1.30pm and 2.30pm throughout the summer. Places cost �3 and must be booked in advance on 01603 624615. Special group tours of the tower (maximum number 20 persons) are available by private arrangement. www.stjohncathedral.co.uk

NORWICH UNDERCROFTS

They are just below street level, a series of vaulted brick and stone structures dating back centuries and the best of their kind in the country. Norwich has more than 70 medieval undercrofts – more than anywhere else in Britain. There are vast brick and stone undercrofts beneath some of our great historic buildings including the Guildhall, Blackfriars' Hall, Dragon Hall and Strangers Hall. Some can be seen as part of the Heritage Open Days in September.

ZOO

The opportunity to get up close to some exotic animals is the big attraction of Banham Zoo's Keeper For A Day scheme which offers a unique opportunity to go behind-the-scenes of the busy zoo. As a temporary zoo keeper — complete with uniform — the events do give you a true feeling of what it is like to work with animals. On a typical day visitors get to cleaning the colobus monkey house and prepare their night feed, feeding giraffe and lemurs and work with the meerkats. The full day experience (10am-4pm) is �270, while the half-day (10am-1pm or 1pm-4pm) is �170. More details on 01953 887771, www.banhamzoo.co.uk

BREWERY

Woodforde's, based in Woodbastwick, is Norfolk's biggest brewer using Norfolk-grown barley and plenty of expert knowledge to produce beers like Woodforde's Wherry and Nelson's Revenge that are a fixture in many of the county's pubs. If you've ever wondered just how they produce all those pints they offer the chance to find out on their special behind-the-scenes tours. They do individual 90-minute tours to see how they make your beer costing �10 per person. Alternatively they do group tours, �80 for 12 people, �160 for 24. Tours include a full guided tour including the history of Woodforde's and the brewing process and — best of all — the chance to sample some award-winning ales. 2012 tours start on March 28. More details on 01603 722218, www.woodfordes.co.uk

LIGHTHOUSE

Happisburgh Lighthouse is the oldest working light in East Anglia. Built in 1790, originally one of a pair - the tower is 85ft tall and the lantern is 134ft above sea level. Today the lighthouse is painted white with three red bands, and has a light with a range of 18 miles. Saved as a working light by the local community, it is maintained and operated entirely by voluntary contributions. The lighthouse is open to the public on occasional Sundays throughout the summer (starting on April 8), entry �3, �1 children. Private visits can be arranged throughout the year for individuals or groups for a minimum donation of �20. There are 96 stone steps winding up the inside of the perimeter wall to the service room directly below the light. www.happisburgh.org

STEAM RAILWAY

North Norfolk Railway runs a 10.5 mile round trip by steam train (vintage diesel trains on some journeys) through the glorious North Norfolk landscape. On selected Wednesday evenings in May and June the Poppy Line will be operating will be operating behind-the-scenes tours of the railway. After a journey along the line from Sheringham to Weybourne, in the company of an expert guide, the tours offer a rare opportunity to have a guided tour of the locomotive and carriage sheds. There will also be an opportunity to visit the signal box at Sheringham.

Tours are planned for May 9 and 23 and June 13 and 27, places �8 per person, which includes the train fare and the guided tours. Pre-book on 01263 820800, www.nnrailway.co.uk

LOTUS FACTORY

We'd all like to get behind the wheel of a Lotus but how about behind-the-scenes of how they are made? The company's hi-tech manufacturing facility at Hethel, is where the world class, high performance sports cars are all individually hand built. The company runs regular factory tours that shed light on the history and heritage of Lotus as well as seeing the cars being assembled, painted and checked. They're the perfect day out for any petrolhead.

Tour places are �39, more details 01953 608547, www.lotusdrivingacademy.com

STATELY HOME

Blickling Hall reopens on February 11 but if you would like to see more than visitors usually get to see keep an eye out for the National Trust's regular programme of 'backstage pass' tours which unveil some of the great hall's hidden secrets, including a servant's tunnel which burrows under the hall's moat. Parts of the historic hall which are usually out-of-bounds are opened to the public with tours of the private rooms usually hidden behind rope barriers, the extensive attics and visit what was once the heart of the hall – the boiler room and coal store. Event dates have yet to be announced but to enquire about tours call 0844 8004308, www.nationaltrust.org.uk

DISTILLERY

You'd think to visit a distillery you'd have to head north of the border — you don't, just head to Roudham. St George's Distillery, home to the English Whisky Co., opened in 2006 and produced its first spirit soon after and has since made well over 1,000 casks which are all maturing nicely in their warehouses. They run two behind-the-scenes tours. The basic tour runs every hour on the hour from 10am-4pm, seven days per week, �5 per person, �2 under-18s. The more in depth tasting tour is led by the chief whisky maker and looks at the distillery and barrel warehouses, followed by an hour of tasting whiskies from around the world, including Norfolk's finest. This normally runs on a Saturday afternoon once a month, �20 per person. Pre-book on 01953 717939, www.englishwhisky.co.uk

FARM

Norfolk is, of course, a rural county and therefore there are loads of opportunities to get closer to the farms that produce most of our food. The best way is on Open Farm Sunday a nationwide event that sees lots of Norfolk farms throw open their gates to visitors. It's a fantastic opportunity to experience the smells of the farmyard and really get in touch with the land that feeds us. This year it takes place on June 17 and local farms taking part include Saham Hall Farm, near Thetford, which will have meet the animal sessions, guided tours and the chance to see farm machinery up close. www.farmsunday.org

CASTLE DUNGEONS

Norwich Castle Museum's tour of the dungeons begins with the usual health and safety checks – plus one you'll probably never heard before. Visitors should be aware that there are stairs, enclosed spaces, a moment of complete darkness…and that anyone who is particularly spiritually sensitive might become distressed. There are said to be ghosts down there, deep beneath the castle where people were held in total darkness for months, chained to walls and tortured. Although these vast stone vaults were built as storerooms for the Norman castle, they were part of the city gaol and for 500 years. From the depths of its sinister dungeons, you can also get a look from the battlements towering above ground level. On a clear day you can see the ridge of hills along the North Norfolk coast. Daily dungeon and battlements tours, �2.40 (�2.10 cons), �1.80 children, 01603 4587, www.museums.norfolk.gov.uk

THEATRE

Ever fancied exploring backstage at Norwich Theatre Royal, having a sneaky peek in the dressing rooms and even trying on the panto Dame costume? Well you can every summer. The theatre runs a special annual free open day every August that includes theatre tours so visitors can have a browse around the building exploring what happens behind the scenes, walk out onto the stage to get a performers-eye view and see what happens at the lighting and sound desks. More details on 01603 630000.

MORE OPEN DOORS…

? Heritage Open Days — Celebrates Norfolk's architecture and culture by allowing visitors free access to literally dozens of interesting properties that are either not usually open. The event, which this year runs September 6-9, also includes tours, events and activities that focus on local architecture and culture.

www.heritageopendays.org.uk

? Norfolk Open Studios — Part of the Norfolk & Norwich Festival, it sees Norfolk artists open up their studios, meet the public and sell works of art. The scheme runs annually in May/June time for two weeks (including three weekends).

www.norfolkopenstudios.org.uk

? Norfolk Garden Scheme — Every year hundreds of gardeners across Norfolk welcome visitors. Most gardens which open for the NGS are privately owned and open just a few times each year. Some open as part of a group with the whole community involved. The gardens give the money raised to the National Gardens Scheme and local charities.

www.ngs.org.uk