Monday 19 March

Having flown up from Bristol, I meet Dom and James, the Assistant Producer, at Glasgow Central train station and we use my sat-nav to guide the hire car to our hotel in Irvine, Ayrshire. Apart from one slight glitch, when we're taken down a road that doesn't exist, the sat-nav performs well and Dom promises to buy one.

The hotel, with its faux Moorish architecture and huge indoor pool with palm trees, has to be seen to be believed; apparently it's popular with flight crews from nearby Prestwick Airport!

There we meet our enthusiastic contributor, Karen Watts of Leeds Armoury (who's going to be talking on camera about the famous mock Medieval Tournament that took place at nearby Eglington Castle in 1839), and our two-man crew, Paul (camera) and Dudley (sound). We'd been expecting a sound recordist called Duncan and it takes a while for everyone (bar Paul) to remember Dudley's name.

I'm in bed by 11, having spent the previous hour reading the script and mugging up on my three pieces to camera. As at Bath, one is quite long, but I've had plenty of time to prepare and I feel reasonably confident.

Tuesday 20 March

Up at 5.15 to make the call time of 6.30 a.m. (which means in the lobby ready to leave). The one golden rule in telly is don't be late, for the obvious reason that time is money. I shower, dress casually in jeans, shirt and sweater (my 'uniform' for the programme), but with thermals underneath.

I've learnt through painful experience always to wear plenty of layers if I'm filming outside in low temperatures. The forecast (correct as it turns out) is sunny but very cold. I meet Dom, James and the crew for an early breakfast (6 a.m.). No sign of Karen. She appears shortly before 6.30, sprightly as ever.

We spend the morning filming chats between Karen and I at various locations in and around Eglinton Castle. I'm well wrapped up in puffa jacket, scarf and gloves. Karen is not so well insulated, and begins to feel the cold as does, less excusably, Dom who's wearing what Paul describes as a pair of dancing shoes.

Once the chats are filmed, I knock off the pieces-to-camera (PTCs), though one, the shortest, has me inexplicably struggling to pronounce the words 'William Marshal'. I put it down to the cold weather! Dom takes pity on my last, sub-standard effort, and moves on to the next item.

Karen leaves to catch a train back to Leeds and at 3 p.m., after a quick picnic lunch, we set off in two cars for Lincoln where we're filming the next day. We arrive at Lincoln's Castle Hotel (all its rooms are quaintly named after castles), at 8.45 p.m. after a nightmarish journey, to be told we're too late for dinner. We head for a nearby Italian restaurant and have a surprisingly good meal. Paul is knackered and goes straight to bed.

Wednesday 21 March

Up at 6.15 for a call time of 7.30. It's cold again and I wear thermals. After filming various PTCs in the beautiful castle (one with me walking on sheet ice around a high tower with hardly any parapet!) we meet our contributor, Professor David Carpenter, who's come to talk to me about the famous – for Medievalists anyway, I'd never heard of it – Battle of Lincoln that was won by William Marshal and his troops in 1216. David is fizzing with energy, particularly when he describes the course of the battle, and very good on the similarity between the tournament and real war.

But his enthusiasm knows no bounds when Dom tells him he's welcome to join us in the afternoon when we go to the offices of the local council to film the Lincoln copy of the Magna Carta (the nobles who forced King John to sign the Magna Carta in 1215 had used an earlier tournament to hatch their plot).

It's normally kept on display in the castle, but is about to be sent to an exhibition in America which is why, luckily, we've got the opportunity to film it outside its protective case. David has never had the chance to examine it, and is anxious to see what's written on the back. It turns out to be the word 'Lincolnia' and was obviously penned by a scribe at Runnymede shortly after the momentous meeting of King John and his nobles in 1215.

We all realize how lucky we are to get access to such a famous historical document – the privilege of making TV.

Magna Carta [Image: Library Of Congress] Copyrighted image Credit: Library Of Congress
Magna Carta

We wrap at 5 p.m. and, having delivered the battered hire car back to a rather bemused local agent (all becomes clear when we tell him we're from the BBC), Dom, James and I catch the 6.17 train to London, arriving at King's Cross at 8.18 p.m. Another short day.

Saturday 24 March

I take the evening train from my home near Bath to London. I've got an early start (a taxi's booked to pick me up at 6 a.m.) and get to bed in my mother's flat near Ladbroke Grove by 11 a.m.

The clocks are going forward and, even with this relatively early bed-time (for me), I'll only get about five hours sleep. As it happens, the neighbours decide to hold an all-night Reggae party and my actual sleep is considerably less.

Sunday 25 March

Up at 4.45 a.m., feeling very groggy. The first bit of filming is indoors, at the Wallace Collection in Manchester Square, but I know museums can be cold and put on my thermals just in case. Taxi arrives early (as ever) and gets me to the Wallace Collection by 6.10! Fortunately the crew (Paul and Dudley) are waiting in their car and I join them while we wait for Dom to turn up.

He's there by 6.30 and we all troop in to Hertford House, the beautiful building which houses the collection, to set up. Dan Walsh, a work experience student from New York University, has brought breakfast, but I'm hardly through my first cup of coffee when I'm called for the first item: an establishing shot of me arriving at the building. That done we film my chat with Dr Toby Capwell, the curator of the Arms and Armour collection and a champion jouster in his own right, who explains how knights in the early days of the tournament (12th and 13th Centuries) would have worn mail rather than plate armour (which came later).

He then invites me to try it out and I'm filmed being dressed from head to foot in a suit of mail by a 'squire' who's had even less sleep than I have. It's incredibly heavy and very claustrophobic to wear, but gradually my body gets used to it. To think people actually fought (in both tournaments and war) in this stuff is mind-boggling.

All kitted up, with mail, helmet and sword, I have another on-screen chat with Toby, and finish off with a couple of PTCs.

We wrap (wrap up/finish) the location at 10 (it's opening to the public) and head for Dom's house in Camden for a late breakfast. After tea and toast we film some more PTCs in Dom's study, and then break for lunch.

At 2.30 we head for location 3 – the Millennium Bridge where we planned to film a couple of PTCs and some GVs (general views) – but it's too busy and, running out of time, we cut our losses and make for our fourth and last location, the Temple Church in the Inner Temple, the site of William Marshal's tomb.

When not chasing off fans of Dan Brown's The Da Vinci Code who are trying to get access to the church which, normally at that hour on a Sunday, is closed to the public – we film exteriors and PTCs. Then we enter the church and film a chat with Robin Griffith-Jones, the Master of the Temple, about the controversy surrounding the identification of the Marshal's tomb. Apparently they're no longer sure which one it is! Griffith-Jones looks splendid in his red robes, and my final PTC about the death of the Marshal, as darkness falls, is very atmospheric.

We wrap at 8.30 and I take a taxi to a friend's house in Wandsworth where I'm staying the night. A very long day (14 hours) and not a murmur from the crew.

Find out more

Was Magna Carta significant - or have we forgotten more important documents of the time?

Explore The Greatest Knight programme

Study history with The Open University