Like old age, travel in eastern Turkey is not for sissies. The tourist must be prepared to shift gears psychologically as well as literally - upward in his expectations of the marvelous works of God and man to be seen, but downward in his anticipation of creature comfort.

The glories of Istanbul, the Hittite Museum in Ankara, the stunning littoral of the Aegean and Mediterranean coasts and the great Classical sites of western Asia Minor are now well established on the tourist track (and have been extensively described in the last couple of decades in these pages). The Turks in those increasingly westernized areas have become used to the yabanci (foreign) visitors and have much improved accommodations and facilities for them. Traveling there is still a long way from grand luxe, but entails no large problems.

Not so in eastern Turkey which, in touristic terms, can be taken to be everywhere east of Ankara, Kayseri and Adana.

The good things first:

The scenery is magnificent, every turn in the road bringing something as beautiful as it is unexpected: glorious forests, streams and gorges; range after range of craggy mountains, some bare, some heavily wooded, culminating in Mount Ararat, towering sudenly from the steppe to almost 17,000 feet, its peak eternally capped with snow; great sweeps of plain, green in the spring, golden in fall.

There are verdant bottom lands, dotted with hamlets, austere, even ugly with their unvarying quadrangular mud brick cheesebox dwellings, but fascinating nevertheless in their sevrity, with cones of cow dung pancakes -- the only fuel on the treeless steppes -- 15 or more feet high. The farmers' carts still move on solid wooden wheels -- or occasionally not on wheels, but only on sledge runners.

The mighty Euphrates, ice-cold from the melting snow of its headwaters, and its companion, the Tigris, dominate much of the region. The traveler is startled to realize that "Mesopotamia," the "land between the rivers," is not merely the fabled area of Babylon, Nineveh and Ur close to the Persian Gulf -- the impression left by the usual school-day reading -- but extends far to the north, within a hundred or so miles of the Black Sea itself. It was those upper banks and not only the lower that witnessed a hundred major episodes of history wrought by the Urartians, Assyrians, Hittites and Alexander's Macedonians, as well as those of the Romans, Byzantines, Seljuks, Ottomans and Armenians.

Even further to the north and east is the great valley of the Araxes, an invasion route for two millennia from its mouth in the Caspian Sea.

For devotees of earlier civilizations there are a host of Urartian sites, such as the two, a fortress and a temple, perched on cliffs above the silky aquamarine water of Lake Van. Thousands of sculptures and artifacts of that civilization and of one of its successors, the Hittite, are to be seen in a dozen provincial museums (with a couple of exceptions, excellently displayed, carefully chosen and unfailingly interesting).

For the Roman ruin devotee, there are the dazzling mosaics of Antakya (ancient Antioch), the 10-arched bridge over the Tigris at Diyarbakir and the black basalt walls of the the city itself, second only to the Great Wall of China as the thickest and strongest in the world. There is the 1st century B.C. sanctuary of Antiochus I of Commagene on the 7,000-foot peak of Nimrut Dag with statues of seated figures so colossal that the visitor himself can sit comfortably between their legs, his head only halfway up their calves. The monarch surveys hundreds of square miles of Upper Mesopotamia in the company of his presumed ancestors, Zeus, Apollo, Hercules and Fortuna, with their accompanying and only slightly smaller eagle totems. In the valley far below, today's road leads across a wonderfully wrought Roman bridge, its columns still upright.

At Urfa, ancient Edessa, one understands how its mighty acropolis, high on its sacred ridge, withstood siege after siege over the centuries: its giant walls protected against attack from one side while a moat, 30 feet wide and twice or thrice as deep, hewn from bedrock, defended the other three.

But fall it finally did to the medieval Seljuk conquerers, themselves illiterate Central Asian nomads, but bringing with them a Persian experience that flowered in fine proportions and infinitely elaborated carvings in the mosques and tombs of Erzerum, Sivas, Silvan, Ahlat, Urfa and Diyarbakir, as lovely as those better known far to the west.

Forty miles south of Urfa, born in a much earlier period, is Harran, a unique town of beehive brick houses to which Abraham migrated from his native Ur of the Chaldees and where he lived until he took it in his head to move on to the land of Canaan.

East of the Euphrates lies the native soil of the Armenians, a people of tragic history whom one comes increasingly to admire and to be gripped by the beautiful constructions they left behind.

The famous early 10th-century church of King Gagik on an island in Lake Van is surely one of the most charming small buildings a designer ever put his hands to. In the perfect proportions of an Armenian chapel -- from which Gothic cathedrals evolved -- the eternal walls carry in high-relief friezes a menagerie of fanciful birds and beasts and deliciously naive Biblical figures: Jonah being stuffed down the sea monster's mouth only to be spewed forth to bliss everlasting in a hammock under a grape arbor; Goliath taking a justifiably dim view of lil' David; that ol' debil serpent tempting Eve.

Far to the east and north of Van, on the Russian border where one may not carry camera or binoculars, is the 9th-through 10th-century Armenian capital of Ani. Only the great walls and a half dozen ruined churches remain, but each is exquisite in proportion and in its restrained but light and airy decoration. The ensemble is unforgettable and in itself worth what was for me this past autumn a trip of 3,000 miles.

And, as intimated above, no easy trip. Turkey has good roads -- I think the best in any not-yet-developed country -- but long stretches are forever under repair -- a bag of cement stimulates a Turk into a frenzy of activity -- so that there are always miles and miles of rocky, dust-choked driving.

With a couple of unjustified exceptions, all hotels in the east are officially rated as fourth class, "simple but clean," which is 100 percent correct on the simplicity, less so on the cleanliness.

In a hotel room there may be a towel, but no toilet paper, drinking glass, soap or reading light. Ice is difficult or impossible to come by. Food is good -- fine vegetables, fruit and bread in abundance -- but the meat is mutton cooked on a spit, savory but monotonous.

The few words of pidgin Turkish that get one by in hotels and on the road in the west are not very efficacious in the east. It is heavily populated by Kurds, not used to tourists and relatively uncomprehending of anyone or anything strange. By old Jewish tradition, they were born of 400 virgins deflowered by a like number of devils. The behavior of their children suggested to me that that genealogy is at least 50 percent accurate.

The mountain cities, i.e. those at altitudes above 5,000 feet, tend to be clean but those on the Mesopotamian plains like Urfa and Diyarbakir are filthy underfoot and elsewhere, and their inhabitants for the most part sullen or worse.

The old Ottoman custom of using the bowstring to eliminate persons whom the sultan disliked and among whom, by the law of averages, were some incompetents, has unfortunately lapsed, allowing certain officials and innkeepers of such cities to survive.

All in all, a venture to the east beyond the now well-marked western tourist paths is infinitely rewarding if you speak some Turkish or have a guide, or go in a package tour, and if you possess the physical and psychological endurance of the young and do not set too much store on comfort and the amenities. Otherwise, travel in eastern Turkey is an idea whose time has not yet come.

The writer, a former managing editor of The Washington Post, has vacationed in Turkey for the last 15 years.