Looking for something different to do to mark Israel's 60th Independence Year? The Ayalon Institute offers history buffs a short but unforgettable trip down memory lane, located less than a 15-minute walk from the Rehovot train station. "Machon Ayalon" (the Ayalon Institute) was the Hagana's code name for a clandestine underground ammunitions factory on the outskirts of Rehovot. The factory operated between 1945 and 1948, camouflaged as a new kibbutz supposedly being established by graduates of the Israeli scouts (Tzofim) on the site of an abandoned agricultural training camp called Kibbutz Hill. It was here that a select group of Palmah members - graduates of the scouts who dreamed of establishing a fishing kibbutz on the Mediterranean coast - patriotically agreed to spend their days in a poorly-ventilated concrete cellar. In three years, they produced two million 9-mm bullets for the homemade British-designed Sten submachine guns that played a critical role in defending the Yishuv in the first stages of the War of Independence, prior to the arrival of 10,000 Czech rifles in April 1948. For 38 years, the abandoned site on the outskirts of Rehovot, back-to-back with the Kiryat Weizmann Science Park, remained pretty much secret. Then the Rehovot Municipality, Israel Military Industries and Kibbutz Ma'agan Michael - whose settlement group had operated the secret facility before establishing the kibbutz itself - banded together to restore the site. While the Ayalon Institute Museum opened to the public on Independence Day 1986, more than two decades later many Israelis remain unaware that it exists. The museum, a cluster of nondescript buildings surrounded by peeling eucalyptus trees that now serves as a Society for the Protection of Nature field school, doesn't look like much. But back in the days when they comprised Kibbutz Tzofim Alef, the buildings' drab Spartan look was part of an elaborate stage setting. For three years, most of the kibbutz members, busy milking cows and minding children, were extras in a drama they knew nothing about. The kibbutz faÃ§ade was only abandoned once Israel declared its independence in May 1948 and arms manufacturing became legal. At the heart of this bogus pioneering venture was the kibbutz laundry, which housed the secret entrance to an eight-meter-wide and 33-meter-long subterranean production floor that had been dug four meters underground. Here the ammunition was manufactured. The hall was accessed through a hole in the floor located under the kibbutz's 15-ton industrial washing machine that lifted and swiveled aside at the touch of a button - once pressed by mistake by a new arrival to the kibbutz who wandered in when everyone was at lunch, wanting to wash her clothes. The machine worked non-stop, doing mountains of laundry not only for the kibbutz members but also for Rehovot residents and a nearby maternity hospital. The noise of the washing machine and the laundry's antiquated hot-water boilers muffled the sound of the 30 bullet-making machines operating below, not to mention a makeshift shooting range employed for quality control tests. The bullet-making machines are a story in themselves. As early as 1931, the Hagana had sent one of its members to learn bullet manufacturing in Germany. The machines were bought as "scrap metal" in 1938 from a defunct Polish ammunition factory by the Hagana's legendary arms dealer, Effi Arazi. Arazi had the machines overhauled and managed to get them out of Poland, although the equipment played hide-and-seek with British Intelligence - only arriving in Mandate Palestine in 1941 after making its way overland in the middle of World War II via Beirut and Damascus. To add a disguising clang of metal to the cacophony created by the laundry operation, a carpentry shop that produced prefabs and a metal shop that made springless metal bed frames - the infamous mitot Sochnut (Jewish Agency-distributed beds) of yesteryear - were set up next door. The metal shop provided, in addition to the din, an explanation for the piles of oil-soaked, metallic-smelling work clothes that hardly could have been dirtied collecting eggs or weeding the kibbutz's vegetable garden. An emergency exit at the other end of the production hall was located under the kibbutz bakery - concealed under a brick oven that, like the washing machine, lifted and swung open at the flick of a switch. Kibbutz Tzofim Alef was surely the sickliest kibbutz in all Mandate Palestine. To discourage visitors, a sign at the gate warned visitors they must dip their shoes in disinfectant, while rumors were artfully spread that the sorry-looking settlement suffered from chronic and repeated bouts of hoof-and-mouth disease. Summer visitors were kept at bay by bogus claims that the kibbutz was being quarantined due to contagious children's diseases. Meanwhile, sun lamps were used to ensure that "kibbutzniks" working underground would emerge as tanned as if they had been out in the fields all day. To avoid having the plant exposed by the sizable amount of electricity the 30 bullet-making machines consumed, the Ayalon Institute simply pirated unlimited juice by plugging directly into the British power grid, leaving no one the wiser. Copper sheeting for the bullet casings was imported under the guise that it was being used to manufacture lipsticks. After the sheets were rolled and stretched into tube shape, the casings were precision-cut by a machine that the workers dubbed the mohel. The gunpowder was pulverized cordite from purloined British artillery shells. A red light in the subterranean production hall was rigged to flash a warning to turn off the machines if spotters saw strangers coming too close to the factory for comfort. The intricate subterfuge worked so well that Ayalon Institute actually only had one close call - a freak coincidence on February 29, 1948, when a train carrying troops from Cairo to Lod was derailed by Lehi mines, killing 28. The Lehi had planted the mines as a reprisal for a car bombing executed by British defectors a few days earlier on Jerusalem's Ben-Yehuda Street - at the entrance to the kibbutz, sending swarms of angry British personnel practically into the surprised kibbutzniks' laps. The kibbutz members rushed out and helped treat the wounded, thus avoiding a thorough search of the premises by irate British authorities. Today, visitors can visit Kibbutz Hill - reconstructed to look as it did in 1943, complete with a vintage-1940s dining room, tin laundry tubs and baggy khaki shorts hanging on the clotheslines - view the original washing machine and oven whose concealment mechanisms are still in working order, and go down to the production floor, where bullet-making machines still stand with some of the original bullets on display. The museum features an educational film in English, Hebrew and Spanish and offers tours in English and Hebrew. There are picnic benches on the grounds, as well. Not far from the Ayalon Institute is another off-the-beaten-track historic site - the Minkov Citrus Museum, situated in a restored fruit packing house on the site of the first Jewish citrus grove, planted in 1904. And only a stone's throw away is the Weizmann Institute and its open-air Clore Garden of Science, which offers some pretty wacky ways of demonstrating scientific principles - a story in itself. For updated information on opening times, entrance fees and directions to the Ayalon Institute call (08) 930-0585. For the Minkov Citrus Museum, call (08) 946-9197.