Both settlements were founded and developed in waterside locations, both were protected from attack by city walls of impressive size and scale. Crucial universal councils which determined the future of the Christian church were held in both settlements, and both İznik and İstanbul boast a church-turned-mosque-turned-museum called Hagia Sophia (Turkicized to Aya Sofya). Then, of course, İstanbul, in its former guise of Constantinople, was the capital of the Byzantine Empire for over 1,000 years. İznik, under its old name of Nicaea was, following the capture of Constantinople by the Crusaders in 1204, the capital of short-lived successor Byzantine state, the Empire of Nicaea. Inevitably, both settlements were to fall to the Ottoman Turks, İznik in 1331, İstanbul rather more famously in 1453.
A visit to İznik is, however, much more than a trip back in time. The lake, which shares the same name as the settlement on its eastern shore, is a serenely beautiful sheet of shimmering blue water wrapped around by folds of forested green hills. It's a verdant landscape, with the flat land on the northern shore carpeted with olive orchards interspersed with stands of peach, nectarine, fig, mulberry, quince, walnut and pomegranate. The reed beds in the shallows are alive with white egret and heron, and squadrons of glossy-black, white-billed coot scud nervously across the silky surface of the lake. Dabchick and great-crested grebe dive beneath the surface in search of carp, kingfishers whirr along the shoreline in azure flashes, and gulls and cormorants give the freshwater lake the feel of an inland sea. It may lack the topographical drama of distant Lake Van, and the surrounding mountains are not as high as those ringing the pearl of Turkey's Lake District, Eğirdir; but this softer, subtler lake is just as attractive in its own right.
Decaying walls, aged tractors and a Roman theater
Still largely confined within its ancient walls, İznik is laid out, as it was when it was founded back in 316 B.C., on a grid plan. What its founder, Antigonus, a general of Alexander the Great, would make of the sleepy town today is anyone's guess. But as a precise, ordered military man he'd probably be shocked at the ramshackle condition of the walls, gently decaying beneath wreathes of creeping greenery, with fig trees sprouting between the cracks and pushing the masonry apart. Aged tractors, many of which look like 1950s relics, left over from the time Adnan Menderes was dishing out these vote catching “wheeled horses” like confetti, are parked haphazardly in the shade of the battlements. The walls, naturally, have been rebuilt several times since 316 B.C., notably under the Roman emperor Hadrian in the first century A.D., then again after the Persians virtually destroyed the settlement in the mid-third century, and again during the reign of the great Byzantine emperor Justinian. Much of what's visible today dates from a massive rebuild in the 13th century during the Empire of Nicaea.
With perseverance it is possible to walk around the entire five-kilometer circuit of the walls, though scrambling atop the walls is a risky undertaking, so unstable is their condition. The trickiest section to negotiate is the northeast sector, between the İstanbul Gate (notable for the two great stone faces, larger than life representations of the masks ancient actors wore onstage, probably taken from the settlement's theater) and the Lefke Gate. For here, the land outside the walls is thick with trees, undergrowth and market gardens. Inside, row after row of small workshops and stacks of poplar timber announce one of the town's chief cottage industries, the construction of packing crates for the fruit and vegetables grown in the rich agricultural hinterland. Just as beneath the great land walls of İstanbul, locals grow their own vegetables and fruit in the shadow of the walls, and on an autumn stroll roadside fires can be seen lit beneath large, flat cauldrons to boil tomatoes down to salça (tomato paste) and grapes into pekmez (grape-syrup).
Outside the Lefke Gate a series of low-slung arches supported the channel, which until fairly recently brought water into the city. There are a couple more gates to pass as you head clockwise around to the Palace Gate, close to the lakeshore. The scenery here is particularly beautiful, with olive groves bumping up against the walls and tangles of wild flowers and shrubs filling in the gaps. Just inside the gate is the Roman theater, built by Pliny the Younger when he was governor of Bithynia in the early second century A.D. Built on flat land, the great rake of the auditorium was supported by massive vaults, still visible today. All the stone seating has disappeared, unfortunately. Worse, graffiti mars the stonework, and local winos clearly use the site as a drinking den.
Tiles, a church and a brace of mosques
Fifty meters or so outside the gate is the İznik Vakıfı, which is helping to preserve the manufacture of the product for which this sleepy lakeside town is most famous for -- tiles and pottery. It is hard to believe today that in the 16th and 17th centuries, what is now little more than an overgrown village was producing the vast quantities of gorgeous tiles used in the Ottoman Empire's capital city to adorn the likes of the Rüstem Paşa and Blue mosques. The İznik Vakıfı is a research institute/workshop dedicated to preserving the original production techniques of İznik tiles and ceramic ware, and hosts visiting groups interested in learning more about producing these great works of art. Casual visitors too can wander around and see how the ceramic pieces are made, look at some prime examples in the on-site showroom and marvel at where the tiles have been used -- everywhere from İstanbul's Tünel to Montreal Peace Park, Canada. So prestigious is İznik ceramic ware that every home here has an İznik pottery style number for their house, and every municipal trash can is adorned with the distinctive white, blue and red patterns of İznik ware.
Continuing clockwise around the walls from the Palace Gate brings you to the lakeshore. Wagtails bob on the sandy shore, and kids paddle in the shallows. There's a fair bit of litter here too, though to be fair this is a nationwide problem, not just an İznik one. A few hotels and pensions line the front, along with pleasantly shady tea gardens and the odd restaurant, and it's easy to while away an hour or two recuperating from the wall walk, sip tea and watch swallows dipping for water as the sun sinks languidly over the lake.
If the walls and the theater are not enough, there are plenty more buildings of historical interest scattered throughout the grid-plan streets. Heading from the shore, through the Lake Gate towards the town center, brings you to the Aya Sofya. It can't compare with its İstanbul rival (few buildings can), but it's pleasantly situated in a garden area complete with palm and fir trees. The exterior of the church, dating back originally to the Justinian-era but completely rebuilt in 1065 following an earthquake, has been so heavily restored it looks almost new. Inside traces of mosaic and marble floor work remain, a faded fresco or two and, more interestingly given how few have survived until today, a synthronon, the semi-circular bank of seating in the apse for the clergy. The attractive brick minaret dates back to the church's conversion to a mosque following the Ottoman take over. North of the Aya Sofya, towards the Lefke Gate, a pair of attractive mosques face each other across a pleasant park. The Haci Özbek Camii has the distinction of being the earliest known Ottoman mosque and the Yeşil Camii is notable for the glazed tiles adorning its slender minaret. Adjacent, in the beautiful Nilüfer Hatun İmareti begun in 1338, is the İznik museum, with a few fine exhibits, including some original Selçuk tile fragments and a couple of wonderfully carved Roman-era sarcophagi.
As a place to unwind after the rigors of big-city İstanbul, this lakeshore town is hard to beat, mixing in equal measure of history, nature and the timelessness of Turkish village life.
How to get there: Regular high-speed catamarans (sea-buses) depart İstanbul's Yenikapı port for Yalova (1 hour, 15 minutes; TL 18). From Yalova quay-front frequent minibuses go onto İznik (1 hour; TL 9).
Where to stay: Budget backpackers' choice is the central, spotless but basic (shared toilets and showers) Kaynarca Pansiyon (Tel.: 0  757 60 25; www.kaynarca.s5.com. Pleasant lakeside mid-range options include the Çamlık (Tel.: 0  757 16 31; www.iznik-camlikmotel.com) and the Cem (Tel.: 0  757 16 87; www.cemotel.com).
Where to eat and drink: The Çamlık Hotel does decent grills (including lake fish) and meze, with lake views. Great köfte are available from bustling Köfteci Yusuf on Atatürk Caddesi. A number of drinking dens dot the center but the best place is Artı, with a small garden on the waterfront east of the Lake Gate.