When considering Jerusalem as a tourist destination, most people think of such holy sites as the Western Wall and the Old City. But on Monday, the city presented a different type of tourism, as corporations around the city opened their doors to 20,000 participants. Timed to coincide with the beginning of schools' Pessah vacation, "Industry Open House" was an opportunity for local businesses, from media to hi-tech, to afford a rare glimpse into their inner workings - all in a kid-friendly way. Children who visited the Kol Record recording studios in Har Hotzvim got a chance to hear themselves making noise, banging the drums and singing into the microphone behind the soundproof glass. Technician David Maimoni explained to the youngsters how albums were made by layering on one element - such as voice, drums or guitar - at a time, similar to the way a layered cake is made by adding dough, chocolate and whipped cream on top. Up the road at Ophir Optics, a maker of precision lasers and lenses, the children from Efrata School eagerly fingered the lenses on display, which were shaped and polished using a variety of techniques. As workers walked by in blue jumpsuits and gloves, production manager Ronen Kraus showed the kids examples of infrared lenses that are oblique to the human eye, but which serve important purposes in night-vision equipment, cameras and other applications. The group of children were also shown a rack of lenses destined for an Israeli spy satellite, and Kraus told them that there were some applications of Ophir Optics products that were so secret that even he did not know them. At Angel's Bakery in Givat Shaul, this reporter met up with a group of families who had already been to the Super Drink bottling facility in Atarot, and spoke enthusiastically of seeing the live broadcast of the news at the Kol Yisrael broadcasting station in Romema. As opposed to most of the companies participating in the one-day open house, Angel's gives tours throughout the year, leading children through the stages of production, from start to finish. Although the bakery's pre-Pessah production is only 50 percent of the usual output of 250,000 rolls and 200,000 loaves, there was still plenty of action on hand. Pipes pumped flour into mixing vats from the mill across the street, and was then mixed with water, yeast, salt and additives in metal containers big enough to hold five grown men. Next, the dough was cut and rounded into loaf-shaped size as it moved along a conveyor belt. Guide Michal Cohen picked up pieces of dough to show kids how to twist them into hallot. That is the one stage of bread baking, Cohen said, which is still done by hand. As the children looked on, an employee, Allam, treated one of them to a "Brand New!" sticker from a roll on hand. Immediately, Allam found himself distributing stickers to the dozens of children who demanded their fair share, too. The kids were held back, though, when shown the VIP rolls, destined for first-class airline meals or the Prime Minister's Office.