After years of wandering among the islands of the south, our lasting memories of Greece were of Greek-flag-colored landscapes, white architectural shapes stark against the light, and darker blues of sky and sea.
But on this trip we flew north to the greener province of Macedonia. From the air, as we approached Thessalonki, vegetation looked shades darker than the olive-leaf hue of things in the south. Stepping down from our plane, we noticed that the air terminal buildings at Thessalonki seemed less luminous than their counterparts seen in the famous Attic light.
Thessalonki, the biblical Thessalonia, and second city in the republic, is the threshold to the Balkans, with Bulgaria and Yugoslavia only miles away. In Macedonia the traveler notices the quicker pace of things and the frequent tallness, the not uncommon fairness, of the man or woman in the street. Perhaps this is the heritage of the strain that produced the sturdy dynasty of Philip II and his world-striding son, Alexander the Great, who grew up at Pella just a short journey out of Thessalonki.
Besides Greeks and proto-Macedonians, Romans, Slavs, and Franks all settled here. And until World War II, 60,000 mostly Ladino-speaking Sephardic Jews were an important element of Thessalonki's population. Macedonian Argyrios Doucas, whose family name, like that of so many Thessalonkins, suggests a Byzantine origin - describes his fellow citizens of the north as a human ''Macedonian salad.''
The spirit of classical Greece is less pervasive here than in the south. In its stead are the monuments to the rule of imperial Rome and the lively ethos of Rome's successors and heirs, the Byzantines. The colossal surviving fragment of the triumphal arch of Emperor Galerius, the Pantheon-shaped rotunda nearby that Galerius thought would be his tomb, and the brick and marble ruins of his palace , are Rome's legacy to Thessalonki.
But what outlasted Rome, as it outlived the long (1430-1912) Ottoman occupation of Macedonia, is the characteristic Byzantine quality of Thessalonki that once, with its profusion of churches and its secular wealth, was inferior only to Constantinople in prestige and imperial honors.
Elsewhere, the display by the door of a church of the Byzantine emblem alongside the Greek colors might seem only nostalgic. In Thessalonki though, on Oct. 26, when the Greek Orthodox faithful converge by the thousands on the 7 th-century basilica of Aghios Dhimitrios, paying homage to the martyred Demitrius, the city's special saint, or when the Greek liturgy is celebrated in Aghia Sophia where thousand-year-old mosaics blazon the dome, the flying of the yellow banner with its crowned double-headed eagle seems plausible, a part of the continuity of ancient things into the present.
Byzantium updated is the way Thessalonkins plant their busy avenues with purple hibiscus trees, the distinctive color of the Byzantines. Consciously Byzantine too, is Thessalonki's porticoed street of the Aristotelous - named for Aristotle, Alexander's tutor - that re-creates the look of the Mese, the vanished main thoroughfare of Byzantine Constantinople.
Where the Aristotelous meets the huge Italianate square of the Platia Aristotelous, the Hotel Electra Palace, with its neo-Byzantine facade, is a perennial favorite with Greek and foreign visitors, and tourists, sailors on leave in their crisp white uniforms, and Paris-tailored Greeks sit democratically together in the many sidewalk cafes, watching the dog-walkers and strollers along the smart waterfront corniche of the Vassileos Konstandinous.
Thessaloniki's uncluttered and well-lighted Archaeological Museum, just across the boulevard from the acres-huge grounds of the yearly International Trade Fair (which opens during the second fortnight of this month for three to four weeks), is a satisfyingly comprehensive time capsule of Macedonian artistic and cultural evolution from the New Stone Age to the exquisite refinement of the Byzantines. An inner gallery, suffused with soft light reflecting from golden objects found in the royal tombs of Vergina, is reward enough in itself for a flying visit to Greece's metropolis of the north.
Pella, Alexander's birthplace only 35 kilometers from Thessalonki, is easily seen in an afternoon. Landlocked now, it was a port where triremes tied up in Philip II's time. What is left of the palatial House of the Lion and of spectacular mosaics alive with mythical scenes, suggests something of the grandeur that was Pella. Alas, the mind is left to fill in what time has erased. We carried W. W. Tarn's slim classic volume on Alexander with us to Pella and reflected on what the Macedonian's biographer has said of his hero: ''He proclaimed for the first time the unity and brotherhood of mankind.'' Just being where Alexander the boy had sat at the feet of Aristotle was better for us than buildings.
Philippi, where Mark Antony and Octavian defeated Caesar's assassins, Brutus and Cassius, at the Battle of Philippi in 42 BC, comes down to us more intact than Pella. The Roman Forum is still there where (Acts 16:11-35) Paul and Silas were seized and ''drawn into the marketplace unto the rulers.'' And so is what tradition calls the Prison of Paul, where Paul and Silas were confined with ''their feet fast in stocks.''
In season, Philippi's Greco-Roman theater goes on doing what it was built for , presenting Greek drama that Paul, no recluse from the world, might have seen on some sunny day almost 2,000 years ago. Beyond Philippi, a peaceful bank and a quiet shallow stream are said to be the place where Lydia and her household were baptized, the first baptism known on European soil.
From Philippi the road goes on through farmlands, California-like in their fertile greenness, until, looking down from a hilltop, with a section of the old Constantinople-to-Rome military road of the Via Egnatia visible below the modern highway, the traveler sees Kavalla lying in its natural amphitheater on this northernmost coast of the Aegean. In Roman times, Kavalla was Neapolis where Paul landed after his sea voyage from Asia Minor. Earlier still, Brutus anchored his naval might here before, like Cassius, falling on his sword after the action at Philippi.
Fishing boats, huge gas lamps projecting like mantis eyes from their bows, tie up in Kavalla in sight of bayside restaurants where the best tables are in the rustic-looking cafe near the fishmongers' stalls. From the port, regular ferries go out to the isle of Thasos.
South of Kavalla and Thessalonki, thrusting seaward between the gulfs of Striminikos and Thermaikos, is the peninsula of Khalkidhiki and its three ''horns'' of Kassandra, Sithonia, and Ayion Oros; this area, enjoying a micro-climate all its own, is spared the rigors of ''mainland'' Macedonia's Balkan-influenced summers and winters.
On the innermost horn of Sithonia, most sheltered of all, an ambitious resort development sprawls along 10 kilometers of beachfront and quiet coves looking on the almost always tranquil Gulf of Kassandra. Like ocean liners moored to the land, the massive futuristic shapes of the Meliton Beach and Sithonia Beach Hotels, space enough for 1,962 guests, dominate a sandy beach where a decade ago nothing here rose higher than a few wind-sculptured pines.
In 1962 Greek shipping magnate John Carras saw the Sithonian coast for the first time and decided then and there to build a holiday resort some day on its vacant sands. Fifty-five million dollars later, Porto Carras has a man-made marina for 150 oceangoing yachts, an 18-hole golf course, a riding stable of imported thoroughbreds, a concert hall, an al frescom theater-cum-cinema, and sea sports ranging from speedboat-parachuting to jet-skiing. For the visitor seeking something more intimate than the stories-high pharaonic-looking public rooms of the Meliton and the Sithonia, a place called the Village Inn caters to their tastes.
From the pleasure domes of Porto Carras, the journey to the Holy Mountain of Athos, only a gulf away, is a time leap back into a world of 10th-century Byzantine asceticism. The Ayion Oros-bound pilgrim - ''tourism'' as such does not exist - disembarks from a coaster he has boarded at Ouranoupolis, steps ashore at the port of Dhaphni where he shows his passport as if entering an independent state. Armed with his preliminary credentials of entry, he rides a marvelously ramshackle bus - a rare concession to the 20th century - to the capital at Kariai, where he presents himself to the police and to the ecclesiastical authorities who issue him a diamonitirionm that, embossed with the imperial double-headed eagle, allows him to wander at will in Byzantium.
One repeatedly says ''he,'' despite modern habit, because women, alas - with one royal exception - have never set foot on Ayion Oros. At least not since Emperor Constantine Monomachus in 1054 forbade access to the ''garden of the Virgin'' to all things female, birds and beasts as well as human. In fact, women can come quite close to Ayion Oros and can even photograph its seaside or cliffhanging monasteries from excursion boats off the peninsula's western coast.
With only four days (the usual stay for most pilgrims) to roam the Holy Mountain, visitors would do well to visit the Great Lavra (Megistis Lavras), oldest monastery on Ayion Oros, and first in the monastic hierarchy; Iviron, which allows more personal freedom for the monks and where even the non-Orthodox can sit with the monks at table and observe them at their devotions, and Xerapotamou, lately less conservative but now on its way to the stern communal life.
The industrial revolution has never come to Ayion Oros and it never will. The forests and the coasts of Ayion Oros remain wholly unspoiled. The sounds that one hears are the sounds of the earth and of the sea, the clatter of the wooden semanthronm (a kind of gong) or the clang of bells.
You turn from Ayion Oros, ''go back to the world'' as its monks say, knowing that much of the meaning of the place will always elude you, as it would have eluded the wise men of Athens in their search for a world built on logic. Practical information:
Olympic Airways has daily flights from Athens to Thessalonki. From its central office on Venizelou Street, Doucas Tours sends history and art buffs out on scheduled trips of discovery to not-too-remote Macedonian historic sites, all of which - taken one by one - can be visited in a leisurely full day or less.