When to visit
Jerusalem can be pretty hot in summer, but not as hot as you might expect, while in winter it can be downright cold and often sees snow. The reason is the city's altitude - though located between the sunny Mediterranean and the scorching Judaean desert, it stands atop a limestone ridge at 780m above sea level, which makes it a good 3C lower in temperature than the coastal plain to its west. Jerusalem is sufficiently mild that the climate is not really a problem at any time of year, and visitors in any season would be well advised to carry at least a light sweater with them. In mid-summer it's dry rather than humid during the day, and pleasantly cool in the evenings. In winter, the city can be wet and cold; temperatures rarely drop below freezing however, and the days often enjoy some pleasantly crisp sunshine. In spring and autumn the evenings can be nippy, but if you want the best weather conditions, late spring or early autumn are the times to visit, between the winter rains and the summer heat.
A more important consideration is the number of other visitors you are likely to encounter, which depends very much on religious festivals. If your reasons for visiting Jerusalem aren't religious, you may well want to to avoid those times of year, since not only are the sights more crowded, but you will find accommodation full and hotel prices extra high.
For Christians, Easter is the prime time of year to be here, with all the sights relevant to Holy Week close at hand, and the time when you may feel it most significant to follow in the steps of Jesus along the Via Dolorosa, and celebrate the Resurrection in the city where it happened. Most of Jerusalem's Christian residents celebrate the Orthodox Easter, which has a rather different flavour to the Western Easter. Christmas is also a popular time to visit, with Bethlehem just down the road and Jerusalem an excellent base to visit from (accommodation in Bethlehem itself will need booking well in advance). From a Christian point of view, the true date of the millennium is December 25, 2000, as opposed to January 1, and those who want to celebrate the 2000th anniversary of the birth of Christ will aim to be here then.
If you are a practising Jew, then to celebrate Rosh HaShannah (the Jewish New Year, usually in September) at the Western Wall is, of course, something very special, but historically the three "foot festivals" of Passover (Pesah), Shavuot (Pentecost), or Succot (Tabernacles) were when the Israelites would come here on foot to worship together in the Temple, of which the Wall is held to be the last remnant. Passover (usually in March or April) is especially popular, as for centuries, Jews at the Passover feast (seder) have promised themselves that they would celebrate it "next year in Jerusalem", and for many the chance to do that is a dream come true. Strangely, even if celebrating seder here, you still say the phrase.
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