Earth Station Goonhilly is the largest satellite station in the world. Its 25 dishes on Goonhilly Downs transmit international news daily from satellites parked 36,000km above the equator. It's where the visionary fiction of Arthur C Clarke becomes fact. With dishes aimed at every continent, almost all epoch-making events enter and leave Britain via Goonhilly - including this year's World Cup. Global coverage of the Apollo 11 moon landing came courtesy of the Earth Station, as did the Olympics, the Rugby World Cup and the Test Cricket from South Africa. Goonhilly even admits to transmitting the Eurovision Song Contest.
The station handles more than 10 million international phone calls a week. If you have ever called the other side of the world the chances are your voice will have been beamed to its final destination via Goonhilly.
It's all pretty amazing stuff: the excitement of science, the practical application of Physics is Fun, chapter 28. The visitor centre is impressively hands-on, interactive and comprehensive. If new technology left you trying to light a Bunsen burner, here's where you can catch up.
Nicola Swanborough took her four children Grace (11), Tom (eight), Florence (six) and Samuel (four).
Nicola: I first visited Goonhilly on a primary school trip in 1970, when there were just a couple of satellite dishes planted in the middle of a field. We'd been to a silage farm en route and the two became intrinsically confused. Nevertheless, the size of the satellite dishes made a lasting impact. "What the hell was that?" I wondered for years after. Now I know. For all that the key action at Earth Station Goonhilly is undetectable to the human eye, the visitor centre makes the whole communication process a visual and digestible experience. More important, it makes it fun.
A people-shuttle with an automated voice-over (or was it a ventriloquist bus driver?) takes you through the security perimeter of the station into the heart of Goonhilly. Sci-fi lights and sounds hijack the imagination, and even if the special effects seem a little bit over-dramatic, they're great for the kids. Star Trek meets Dr Who.
Disappointingly, you can't poke a terrestrial nose inside the operations control room where it all really happens. This is for security reasons, although I suspect that the image of earthlings dunking digestive biscuits in their chipped "I love Cornwall" mugs would shatter the sci-fi image.
Other attractions include a journey through space and time in a small, futuristic theatre, the chance to surf Cornwall on dry land at the Internet Zone and the opportunity to operate an antenna for yourself.
The centre sells astronaut snacks, but it does a good cup of tea, too.
There's an excellent bookstall in the visitor centre - and I wish I had invested in some sort of satellite bible. A day at Goonhilly throws up a lot of follow-on questions, especially from the children, and it would have been useful to have had some sort of back-up.
Grace: I didn't really expect to enjoy Goonhilly, but it's actually very interesting. It's one of those places that is educational but fun too. We had often driven past the satellite dishes in the car, but it is not until you get close up that you realise how enormous they are.I like the fact that they have named the dishes after characters from the Arthurian legends; I particularly like Arthur, Guinevere and Merlin. Although they are modern, they suit their ancient names.
It is interesting, too, that Goonhilly is only a couple of miles from Poldhu Cove where the first live transatlantic message was sent in 1901 from Marconi's receiver to a receiver on the coast of Newfoundland. It is nice to visit there, too, and see where it all began.
Tom: I'm really interested in satellites and space and how information can be beamed across the world, so it was mega cool to see the dishes up close. In fact, though, I think they look best from a distance, especially with a sunset behind them. They're really beautiful.
I can't say I understood everything: I mean how it all happens so quickly, and without being able to see the signals themselves beaming in from space. There's lots to do inside the visitor centre and there are some great satellite pictures of different parts of England to look at. I really enjoyed the Internet Zone, although it tends to get quite crowded.
Florence and Samuel: Can we go to the beach now?
Location: Goonhilly Downs, Cornwall, seven miles from Helston on the B3293 St Keverne Road.
Opening times: 10am-5pm, 1 April to 14 June; 10am-6pm, 15 June to 17 September; 10am-5pm, 18 September to 13 November.
Cost: Adult pounds 3.99, senior citizens and students pounds 2.99, children 10-16 pounds 2.50, children five to nine pounds l.99, four and under free, family ticket (two adults and two children) pounds 10.
Facilities: visitor centre, family restaurant, outdoor children's area, gift shop, picnic benches.
Tip: when the weather is bad, everyone tends to descend on Goonhilly, making it crowded and almost guaranteeing the prospect of long traffic queues. It really is worth combining it with a beach trip along the Lizard on a sunny day, when you will be able to appreciate a panoramic view of Goonhilly as well as a close-up tour.