Mosque of Mahmut Bey, Kasaba, near Kastamonu, Black Sea region
Kastamonu is something of a museum in itself. Ottoman mansions perch on rocky outcrops and ancient Paphlagonian tombs are carved into the cliffs. The nearby coast is unspoilt by motorways or tourism – perfect for exploring. The Mahmut Bey mosque, in the tiny village of Kasaba, a half-hour drive north-west of Kastamonu, is a real masterpiece. It was built in the second half of the 14th century, and the motifs painted on its elegantly carved wooden columns are still vibrant after 650 years. It is one of Turkey's very few surviving monuments from the Beylik period, when warring principalities competed for the scraps of the declining Selçuk and Byzantine empires.
• In Kastamonu, stay in either the Ugurlu Konarklari or Toprakçilar Konaklari (kastamonukonaklari.com, B&B doubles from €60)
Great Mosque and Hospital of Divrigi, Central Anatolia
A Unesco world heritage site, this 12th-century Selçuk mosque complex is a masterpiece of stone-masonry. Each exuberant entrance attests to a whole mess of influences on the carvers who designed it, from all around its location in the remote Upper Euphrates, in the Central Anatolian region. You can't fault their work. The floral motifs seem to leap from the stone, and the geometric designs are unbelievably intricate. You can see some of the mosque's original carpets – the oldest in the world – at the Vakiflar Carpet Museum in Istanbul.
• Divrigi is a three- to four-hour drive from Sivas airport. Accommodation there is limited, but try the Divrigi Belediye Oteli (divrigi.bel.tr/belediyeotel.aspx, doubles from €20). For information on the Great Mosque, see tinyurl.com/mosquedivrigi
Selimiye mosque, Edirne, Marmara region
Istanbul was the Ottomans' third capital. The previous one, Edirne, continued to be very important after the fall of Constantinople and it was here, in 1575, that Sultan Selim II asked the legendary architect Mimar Sinan to build him a mosque. It is Sinan's masterpiece. The enormous dome soars almost impossibly high, supported without disruptive piers in the prayer hall – unlike the interior structure of Istanbul's Blue Mosque. It is filled with light from dozens of stained glass windows. Edirne is three hours from Istanbul, near the Bulgarian and Greek borders.
• Stay in the Efe Hotel (efehotel.com, doubles from €60). For more information on the Selimiye complex, see archnet.org
Sagalassos, Mediterranean region
High in the Toros mountains, the ancient city of Sagalassos is not the most accessible classical site in Turkey. Good thing too. Unlike so many others it was spared the attention of looters. The star exhibit in the British Museum's 2008 Hadrian exhibition – an enormous marble statue of the ruler – was found here just a year earlier. Few tourists drive the 100km here from Antalya, but those who do will find ruins to rival the better-known sites along the south coast.
• In Antalya, stay in the Tuvana Hotel (tuvanahotel.com, doubles from €120). Day trips from Antalya start at €50pp with Turantalya (turantalya.com). Avis (avis.com.tr) car hire from Antalya starts from around £42 a day
Kartalkaya Ski Resort, Bolu, Black Sea region
With mountains galore and reliably snowy winters, skiing is an obvious choice of pastime in Turkey, but one that has been slow to attract a dedicated following comparable to Europe and North America. This means that at Kartalkaya, one of the best-developed resorts in the country (near Bolu, between Istanbul and Ankara), the gentler slopes are crowded with day-trippers, while the powder goes untouched, save for a few more experienced skiers and snowboarders. After a few days you might exhaust the relatively small ski area, so go exploring. There are scenic lakes – frozen in winter – and Bolu is renowned for its cooks and cuisine.
• Stay at the Dorukkaya Otel (dorukkayaotel.com, from £104 for a half-board double). For equipment hire and day-trip advice from Istanbul in English, contact Emre at Freedom Sports in Beyoglu (+90 212 244 7223, freedomsports.net)
Michael Hornsby is Istanbul bureau chief for lifestyle magazine Cornucopia (cornucopia.net). For the best hotel rates throughout Turkey, see cornucopiahotels.com