The Gallipoli peninsula, across the Dardanelles from Çanakkale, was the site of one of the great Allied failures of the First World War — and one of the foundational events of modern Australian, New Zealand, and Turkish national identity. The 1915 campaign cost over 250,000 lives on each side; the trenches, cemeteries, and memorials are preserved across a long stretch of coast and ridge as the Gallipoli Peninsula Historical National Park.
The main sites — ANZAC Cove, Lone Pine and Chunuk Bair, the Çanakkale Şehitler Anıtı (Turkish Martyrs' Memorial), and the Helles Memorial at the southern tip — are spread over a long line and very hard to do without transport. Most travellers either join a small-group tour from Çanakkale or Eceabat (around 8 hours, lunch usually included) or hire a car. Anzac Day, 25 April, sees thousands of antipodean pilgrims and an overnight dawn service; book months ahead if you want to come then.