ISTANBUL (AP) — The World War I battlefield of the Gallipoli campaign, where throngs gather each April to remember the fallen, is a place of lore, an echo of ancient warfare that took place on the same soil. Now researchers are mapping dugouts, trenches and tunnels in the most extensive archaeological survey of a site whose slaughter helped forge the identity of young nations.

Armed with old maps and GPS technology, the experts from Turkey, Australia and New Zealand have so far discovered rusted food cans, unused bullets and their shell casings, and fragments of shrapnel, Ottoman-era bricks with Greek lettering, ceramic rum flagons of Allied soldiers and glass shards of beer bottles on the Turkish side. They announced early findings ahead of annual commemorations on the rugged peninsula on Sunday and Monday.

The chief aim is to gain a detailed layout of a battlefield whose desperate trench warfare, with enemy lines just a few dozen meters (yards) apart in some places, has been recounted in films, books and ballads, acquiring a legendary aura in the culture of its combatants....