Istanbul - More than 1 million flag-waving Turks gathered in Istanbul on Sunday for an anti-coup rally to mark the end of nightly demonstrations since the July 15 abortive military insurrection that left more than 270 people dead.The Yenikapi meeting area at the Marmara Sea waterfront in Istanbul's European side was transformed into a sea of red and white, the colours of Turkey's flag. The "Democracy and Martyrs' Rally" was billed as a cross-party event representing Turkish unity in the wake of the failed coup in which a group of renegade military officers attempted to seize power with tanks, helicopters and fighter jets.No official estimate has been provided, but Turkish media said millions were attending.Religious leaders and two of Turkey's three opposition parties were attending, sitting next to President Recep Tayyip Erdogan, who arrived on board a helicopter with his wife Emine. The pro-Kurdish People's Democracy Party, or HDP, wasn't invited.The event kicked off with a minute of silence for those killed while opposing the coup, followed by the Turkish national anthem and a recitation of prayers.Giant screensA 60m stage was set up for the event, framed by two platforms and draped with massive national flags and banners depicting Erdogan and Turkey's founding father Mustafa Kemal Ataturk. A roll call of those who died opposing the coup was read out as the event began.Construction cranes suspended giant Turkish flags beside the meeting area, while flag-draped boats and yachts zipped back and forth along the water.Following the abortive putsch, the Turkish government has been encouraging nightly anti-coup rallies in all of the country's 81 provinces as well as in certain foreign locations such as Cologne, Germany.The event was being simultaneously broadcast on giant screens in all of Turkey's provinces and crowds of thousands gathered to watch in the country's major cities.Nearly 15 000 police were providing security at the event. Anti-aircraft batteries were also set up at the event grounds, while two helicopters circled overhead.Party bannersThousands of buses and more than 200 boats were commissioned to bring attendees to the area, where they passed through one of 165 metal detectors before being given hats and flags. Those wounded during the attempted coup and the families of those who died, were given special passes for a seated area.Erdogan urged people to bring only the Turkish flag instead of party banners."There we will stand together as a single nation, a single flag, a single motherland, a single state, a single spirit," he said Saturday in comments carried by Turkish media.An Ottoman marching band entertained the crowd before the official start of the event, with 240 members representing the number of those authorities say gave their lives fighting off the coup.