Collectors of antique maps tend to be male, which may have something to do with comedienne Roseanne Barr's observation that: "Men can read maps better than women because only the male mind could conceive of one inch equalling a hundred miles."
But women are becoming increasingly interested. "The majority of map collectors are male but I'm selling more and more to female buyers now," says Daniel Crouch of the Shapero Gallery in London. "Maps are often bought for their decorative value, as they can be more compatible with modern interiors than, say, old masters."
Antique maps are not simply beautiful to own, they also represent a sound investment. "Maps have rocketed in value over the past 15 years," says Mr Crouch. "Maps that sold for about £100 at the end of the Eighties are now worth about £1,000. However, it's still a relatively inexpensive thing to collect, compared with other antiques that people go for."
Not even the arrival of maps on the internet has dampened the enthusiasm for antique examples among serious collectors, although it has affected the very bottom end of the market.
"The better maps have risen steadily [in value]," says Philip Curtis of The Map House, also based in London. "Better-quality items have always increased proportionately more in this sector. It's a good investment because there is a finite supply of good old maps but the demand is increasing."
Not surprisingly, perhaps, apart from age, condition and rarity, geography greatly affects the value of a map. "Everyone has an interest in where they come from," says Mr Crouch, "and it's easy to sell someone a map of their house or their own area. World maps are the most valuable because they have a universal interest."
Very old maps of the world, in good condition, are especially valuable. The Shapero Gallery recently sold a pre-Columbus Ptolemaic map, ascribed to Taddeo Crivelli - although it won't disclose the price.
The biggest and wealthiest collectors are American, as is the case with most areas of collecting. Maps of the Americas therefore have the highest potential value, followed by those of Europe and the Far-East.
"Interestingly, economic or political uncertainty can seriously bring down the value of a region's maps," says Mr Curtis. "The Middle East is of less interest to collectors at the moment. Fifteen years ago, when its economy was strong, maps of Japan were the fastest-growing area in map collecting. Now the country has been through a long and extended slump, their value has dropped off."
The Shapero Gallery is currently offering a set of the Victorian social commentator Charles Booth's "poverty maps", dating from 1891. These depict all the roads in central London, colour-coded to show the financial status of the inhabitants at that time. The set of four maps in their original folder are worth around £2,000.
Also on sale are individual playing cards from the reign of Charles I, each depicting a different British county. The King of Hearts (with the head of King Charles himself) shows the county of Middlesex and is worth around £500.
The Stuarts were clearly great fans of cartography. The gallery also has an example of the earli- est folding map, from 1644, called a quartermaster's map. It shows every building in each county in which you could quarter soldiers. It is on sale for £5,000.
While you can part with thousands of pounds for a map, it is also possible to pick up good-quality items for under £100. "You should buy the best you can afford, although this won't necessarily be the most expensive if you are serious about collecting," says Mr Curtis. "It's better to buy a lovely example of an inexpensive map than a poor example of an expensive one."
Ironically, the older the map, the more likely it is to survive. Maps printed before 1800 (the earliest printed maps came out around 1477) were produced on rag paper, which is far more robust than the pulp-based paper that modern maps are printed on.
As with any other collection, the more knowledge you have, the more successful you are likely to be. The best place to find out more about maps and map makers, apart from one of the many sales that happen throughout the year, is the Royal Geographical Society in London, which has the largest private collection in the world.
Its Map Room is currently closed for renovation but will reopen in June; members of the public can examine and use its collection for £10 a day. You can even buy copies of some 19th- to 20th-century maps from as little as £3 each - nice to have, but not quite the same as owning and gazing at the real thing.
HOW TO START OFF IN THE RIGHT DIRECTION
From just under £100 for a good antique map to around £100,000 for something very special.
* The Map House, 54 Beauchamp Place, London SW3 (020 7589 4325).
* The Shapero Gallery, 24 Bruton Street, London W1 (020 7491 0330).
* The Royal Geographical Society, 1 Kensington Gore, London SW7 (020 7591 3000).
* www.map-fair.com (lists map fairs worldwide).
* www.harvey27.demon.co.uk/imcos (website of the International Map Collectors' Society).
* 5-6 June: International Map Collectors' Society London Map Fair, Olympia Exhibition Centre, London W14.
* 8 June: The Map Room at the Royal Geographical Society reopens.
* 9-15 June: Grosvenor House Art and Antiques Fair, Park Lane, London W1.Reuse content