( CNN ) -- It was once that a cassock , a simple cross and a chalice was all you needed to equip the average church , but now the world of liturgical accessories is a big business . Poland 's SacroExpo is one of the largest trade fairs of its type in the world , hosting displays of everything from bells to church alarm systems and evangelical multimedia . `` We 've even had electronic Bibles and electronic rosaries , confessional boxes with air-conditioning and heating and special priest vestments equipped for war zones , '' explains Andrzej Mochoń , President of Targi Kielce , the organizer of SacroExpo . `` The electronic Bibles have been especially popular with the elderly , '' he says , referring to the pocket PC-like devices which speak the Old and New Testaments . The trade fair , now in its 13th year in the Polish city of Kielce , is officially called the International Exhibition of Church Construction , Church Fittings and Furnishings and Religious Art . It brings some 300 exhibitors from 15 countries and is now a fixture on the religious circuit . It attracts some 5,000 visitors -- most of these accredited clergy who are in the business of outfitting churches and priests with the accoutrements of the First Estate . Globally the industry is worth an estimated $ 4 billion and runs from big ticket items like expensive musical instruments such as church organs to simple wooden rosary beads , which can sell for as little as a few dollars . `` Probably one of the most expensive everyday item for a church would be a chalice for taking communion , '' says Mochoń . `` These can be works of art made of silver or gold and new ones are made in workshops in Germany , the Czech Republic or Italy . '' Send in your best images of Poland . Some of the strangest items on the exhibitors ' stands are church vestments designed for missions to war zones such as Afghanistan . These include camouflaged cassocks . `` It 's also made of special material to withstand very extreme temperatures , '' says Mochoń . There are also highly colored vestments for African priests and plain black favored by Poland 's local Catholic priests . Other items include electric candles , automatic church bells and even heated pews . The company that sells the pews , Polarheat , says that when the temperature in Poland drops to minus 10 degrees celsius it can be as cold as minus 15 in many churches . `` At that temperature , even the communion wine freezes , '' says a company spokesman . `` It can be pretty uncomfortable . '' Renewable energy is also becoming increasingly popular to heat church properties , according to Mochoń , not least ancient cathedrals which , because of their cold stone , high Gothic arches and vast planes of stained glass windows , are some of the most notoriously cold places in many European cities . Other exhibitors point to new directions for the Catholic Church . A wine company that sells communion wine for Holy Mass reports that priests are favoring whites over reds because the colorless liquid does not make stains on white robes . The showpiece at last year 's event was the reconstructed 18 meter-long `` popemobile '' of Pope John Paul II . As well as devotional articles , such as crucifixes and sacral art , the trade fair is also an acknowledgement that churches , especially historic cathedrals , can be expensive to run and need skilled craftsmen to maintain . Among the services displaying at the expo are internal architects , landscape gardeners , experts in cemetery maintenance and craftsmen that specialize in the manufacture of bells . Other services include agents for religious tourism and pilgrimages . Pilgrimages to sites of special devotion have been a big business since the Middle Ages , but the ability of people to travel easily and cheaply has seen Catholic pilgrimages grow into a multi-billion dollar industry . Lourdes in France , believed to be the site of several miracles , regularly attracts more than 5 million pilgrims a year , only slightly below the number one Catholic destination , Rome .
CNN in Rome each Last year 's is one of world 's largest church trade shows . From electronic bibles to heated pews , ecclesiastic accessories are available . Industry supplying church items is estimated to be worth an estimated $ 4 billion . Last year 's highlight was a full reconstruction of Pope Targi Kielce 'popemobile '