This is a memorable, varied and demanding full-day hike. Beginning less than 20 kilometers from Jerusalem, the path makes its way through three quality hiking areas: the Sorek Valley, the Ktalav Valley and the Ma'ara Valley. It starts 600 meters higher than it finishes, so it's generally downhill, with the exception of the short climb out of the Ktalav Valley to Bar Giora. Well signposted throughout, you will have to carry your own water, as the supply en route is quite unreliable. From the bus stop at the entrance of Moshav Ramat Raziel, follow Route 395 eastward for about eight minutes, up to a wide, black-marked trail heading south. That track becomes aromatic in the spring months, as the marjoram, sage and thyme flower. It is bordered with one of the few natural pine forests in the Judean Hills; most of the others were planted by the Jewish National Fund. The narrowing track offers an uncanny feeling of going through the hills rather than over them. As it skirts Mount Pitulim (the double-domed "twisted mountain"), you'll get a secret sense of relief that you don't have to pull up to the top quite so soon. A splendid view opens out to the west, framing the lowland beyond the Judean Hills inside a very wide V. After about an hour of hiking, the trail enters the Sorek River Valley, along a sharply inclined concrete water pipe. The intrepid might slide down, it would be excruciatingly painful for most sensible hikers. Cross over the Sorek on the metal bridge. Do not swim! The river contains a fair amount of west Jerusalem's sewage. Pass under the railway and explore the old (now unused) Bar Giora railway station, halfway between Jerusalem and Beit Shemesh. The new sign is brash, and the old sign is fading. Be sure to take a picture before it becomes totally illegible. It is one of the few double-tracked portions of the Jerusalem-Mediterranean coast railway, where trains to and from Jerusalem may pass one another. Take the green-marked path which leads up the Ktalav Valley. Ktalav, by the way, is Hebrew for "strawberry tree." Its reddish bark peels off easily, and its leaves fairly glisten. It is a spring bloomer with sweet-tasting berries that ripen year-round; get in line before the birds strip them bare. There is a famous Arab legend which tells of a shepherd and his father falling in love with the same beautiful girl. The besotted and infatuated son took a heavy stick and beat the older man to death. Out of the blood-soaked staff sprouted the red-barked tree, which immortalized the father. Ktalav is from the Arabic "katlib," which means "killed father." The green-marked trail zigzags its way up long-neglected and overgrown ancient farming terraces to the domed remains of a pre-1948 Arab village, centered around the tomb of the locally venerated holy figure, Sheikh Bader. It continues to wend and wind upward, becomes black-marked and eventually climbs out of the Ktalav Valley on the only major incline of the day, ending up at the parking lot at Bar Giora junction, on Route 3866. It's a good spot for a well-earned halfway rest. Turn right, and walk along Route 3866. After about 10 minutes, a red-marked route to the left starts its eight-kilometer westward trail down Nahal Hama'ara - the Cave Valley - so named for its large cave on the northern side. Follow it the entire length, to the terminus of the hike. Beit Attab, an abandoned Arab village built on a Crusader fortress, appears on your left, after a half-hour of gentle descent. The red-marked path pushes upward to nearly 700 meters, giving the opportunity to explore the vicinity with care. The Crusader fortress was excavated in 1962. Search for the remains of an olive press and a secret tunnel. Also, look out for the tomb caves on the southern slope, which are thought to be from a pre-Crusader Jewish settlement. The trail narrows and steepens, and within another half-hour reaches Ein Sufla - Sufla Spring. Here the descent becomes tricky, though not dangerous, and it should be negotiated slowly, step by step. The actual spring is covered by large oak and carob trees. Those with some remaining energy might change clothes and crawl through the short but challenging narrow passageway leading to the spring source. From here onward, the final four kilometers are downhill and mainly on the streambed. Progress is not fast. The surface is ridden with potholes created by the seasonal fast-flowing water eroding the karst-based riverbed with swirling stones. The sheer speed and power of the stream in full flood has also worn down rock precipices into a series of slides, which you may care to test personally. The typical Mediterranean vegetation features oak trees, with daisies blooming in early winter, and rock-roses in late spring. Under no circumstances should you attempt this section in the dark. It is that fluvial erosion which appears to have exposed the Teomim Cave, indicated by signposting on the left side. This large natural cave, nearly 100 meters in length, was the most popular cave in the Judean Hills until the opening of the Sorek Stalactite Cave nearby. Entry is forbidden between November and March, when the cave's permanent residents, a large fruit-bat population, are in hibernation and must not be disturbed. These bats, by the way, eat only ripe fruit - and fruit is generally picked unripe. The bats get the leftovers on the trees after the harvest. Formerly, ripe fruit was the breeding ground of the crop-damaging Mediterranean fly. Fruit bats thus keep their population down. Soon after the cave, the trail widens out and Moshav Zanoah and Route 3855 appear in front of you, marking the end of the hike. Three kilometers to the north is plenty of parking, but there are no buses to Beit Shemesh. Those without transport might consider hitching at the entrance of Moshav Zanoah.