Old Testament
From the Old Testament and from existing remains a good idea may be formed of the appearance of such a place of worship. It was often on the hill above the town, as at Ramah (I Samuel 9:12-14); there was a stele (matzevah), the seat of the deity, and a wooden post or pole (asherah, named after the goddess Asherah), which marked the place as sacred and was itself an object of worship; there was a stone altar, often of considerable size and hewn out of the solid rock' or built of unhewn stones (Exodus 20:25; see altar), on which offerings were burnt (mizbeh, lit. "slaughter place"); a cistern for water, and perhaps low stone tables for dressing the victims; sometimes also a hall (lishkah) for the sacrificial feasts.
Around these places the religion of the ancient Israelite centred; at festival seasons, or to make or fulfil a vow, he might journey to more famous sanctuaries at a distance from his home, but ordinarily offerings were made at the bamah of his own town. The building of YHWH's singular Temple at Jerusalem, which (under the Law of Moses) had a patent on sacrifices, did not stop the bamot sacrifices until Kings Hezekiah and Josiah proscribed them.
The prophets of the 8th century BC assail the popular religion as corrupt and licentious, and as fostering the monstrous delusion that immoral men can buy the favour of God by worship; but they make no difference in this respect between the high places of Israel and the temple in Jerusalem (cf. Amos 5:21 sqq.; Hosea 4:1-19; Isaiah to sqq.). Hosea stigmatizes the whole cultus as pure heathenism—Canaanite baal-worship adopted by apostate Israel. The fundamental law in Deuteronomy 12:1-32 prohibits sacrifice at every place except the temple in Jerusalem; in accordance with this law Josiah, in 621 BC, destroyed and desecrated the altars (bmoth) throughout his kingdom (where Yahweh had been worshipped since times before a permanent singular Temple at Jerusalem was erected) and forcibly removed their priests to Jerusalem, where they occupied an inferior rank in the temple ministry.
In the prophets of the 7th and 6th centuries BC, the word bamot connotes "seat of heathenish or idolatrous worship"; and the historians of the period apply the term in this opprobrious sense not only to places sacred to other gods but to the old holy places of Yahweh in the cities and villages of Judah, which, in their view, had been illegitimate since the building of Solomon's temple, and therefore not really seats of the worship of Yahweh; even the most pious kings of Judah are censured for tolerating their existence. The reaction which followed the death of Josiah (608 BC) restored the old altars of Yahweh; they survived the destruction of the temple in 586, and it is probable that after its restoration (520-516 BC) they only slowly disappeared, in consequence partly of the natural predominance of Jerusalem in the little territory of Judaea, partly of the gradual establishment of the supremacy of the written law over custom and tradition in the Persian period.
The rule of the Law of Moses that sacrifice can be offered to Yahweh only at the Temple in Jerusalem was never fully established in fact (just as the entire Law of Moses was never established in real life). The Jewish military colonists in Elephantine in the 5th century BC had their altar of Yahweh beside the highway; the Jews in Egypt in the Ptolemaic period had, besides many local sanctuaries, one greater temple at Leontopolis, with a priesthood whose claim to "valid orders" was much better than that of the High Priests in Jerusalem, and the legitimacy of whose worship is admitted even by the Palestinian rabbis.
Read more about this topic: High Place