TEARS OF CHIOS
I travel 25km south of Mesta to Pyrgi's nearby Chios Mastic Museum, set on a hill overlooking a grove of gnarled mastic shrubs growing in neat rows. From its excellent exhibits, I learn that cultivating mastic is laborious.
Preparations begin in June when the twisted branches and trunk of each tree are cleaned and wiped, while a circle of white clay powder is strewn on the ground around it to catch the drops of resin as they fall.
A month later, the trunks and branches are scored with a sharp tool. Incisions are carried out weekly over six weeks.
It takes a fortnight for resin to drip from every round of scoring, falling onto the ground in the shape of teardrops, hence mastic's nickname as the "tears of Chios".
Collection of the drops is done once they have hardened between 15 and 30 days. The gathering takes place at dawn before the sun's rays soften the gum.
Villagers then sort out the coagulated drops, cleaning them of dirt and leaves, and washing them. This takes all winter and brings communities together.
It is hard work, but the returns are great. The mastic trees yield resin after five years of growth and for the next 65 years. Although the yield from each tree is small, up to 150g, a 5g bottle of mastic essential oil retails at €30 (S$47).
In Pyrgi, it is time to explore this fortress village. Virtually every building, including its church, is covered in black-and-white geometric patterns using a scraping technique known as xysta.
Introduced possibly by the Genoese, black sand brought in from the nearby volcanic-sand beach of Mavra Volio is plastered on the buildings, then layered with white lime before it is hand-scraped to create various shapes, which are reminiscent of the Italian sgraffito, a decorative Renaissance art style.
Wandering in the alleyways of Pyrgi evokes the same timeless feel as in Mesta. But Pyrgi is more compact; the cobblestone lanes are narrower and the walls higher. Like Mesta, it was built out of sight from the sea with a central tower for villagers to converge in times of danger, accessed across rooftops.
COSMOPOLITAN CESME
As unique as Chios is in Greece, as it is only on this island that mastic has been successfully cultivated, there is another place that mirrors it and that is Cesme in Turkey. It is just 15km across the Aegean Sea, on the coast of Turkey.
Like Chios, Cesme has the same microclimate and soil conditions conducive for mastic cultivation.
But unlike its Greek counterpart, production has always been limited, although plans are afoot to plant more mastic trees. The Turks use their gum to flavour sweets such as Turkish delight and for making its popular sticky ice cream.
But Chios has more in common with Cesme than mastic. They have a shared culture and history.
In ancient times, this coastal town bore the Greek name of Cysus. Once a fishing village, it was renamed Cesme, meaning "fountain", after the many natural healing springs in the area. Like Chios, Cesme was plagued by pirate attacks and a Genoese castle was built in 1508 to repel them.
Today, the hilltop castle dominates the city centre. I walk along its ramparts for panoramic views of Cesme and visit its archaeological museum, which has artefacts tracing the settlement's origins to as early as 196BC during the Roman era.
As holiday destinations, Chios and Cesme are intertwined as they make natural springboards for each another. It is easier and cheaper to get to Chios by ferry from Cesme than to fly from the Greek capital, Athens.
Cesme matches the sophistication of Chios Town with a marina similarly crammed with sleek yachts and surrounded by trendy bars and restaurants. It also has a seafront promenade for viewing glorious sunsets and lined with traditional Turkish wooden gulets offering day cruises to offshore islands for swimming and snorkelling.
But what makes Cesme special is its Mediterranean flavour, thanks to its stone houses with terracotta roofs. They make for a picture- postcard scene around the marina and harbour set against a backdrop of verdant mountains. The soaring minaret of a nearby mosque adds a distinctive Turkish touch.
Away from these houses, many of which are holiday homes of well-to-do city dwellers in nearby Izmir and Istanbul, is Cesme's old quarter, with its traditional Ottoman houses with wooden balconies and a 16th-century caravanserai that has been restored into a 29-room boutique hotel (www.cesmekervansaray.com.tr).
HEALING NATURAL SPRINGS
I seek out Cesme's famed healing springs at Ilica. A popular resort with sandy beaches and shallow waters, the thermal springs ooze direct from the seabed.
In a corner of Ilica Harbour, I walk down a rickety flight of steps to join several swimmers in an enclosed section of the sea to experience the sensation of hot mineral waters bubbling up to the surface and mixing with cool ocean water to provide a pleasant warm soak.
Later, at the Sifne Termal & Hotel (admission: 25 Turkish lira or S$10, www.cestur.com), I soak in its two outdoor thermal pools of different temperatures and discover the reason for the springs' allure.
On a board is a long list of minerals in the water, such as sulphur, iron, sodium, magnesium and calcium - all good for the skin and for curing body aches - and to which Ilica, meaning "hot springs", owes its name.
To slip into a soothing spring is a true Mediterranean pleasure. So it is little wonder that Cesme - and Chios - are the Aegean's twin coastal gems.
•Tan Chung Lee is a freelance travel writer who explores Europe from Turkey every year.