Two thousand municipal leaders from across Canada are gathering in Niagara Falls this weekend for an annual meeting.Russ Powers, the head of Ontario Municipalities, says because the meeting is in a tourist destination — Niagara Falls — this year’s conference lured a particularly big crowd. Today’s big draw was the keynote speaker, federal Liberal leader Justin Trudeau.But Calgary mayor Naheed Nenshi has been getting the most online attention for a photo he tweeted yesterday.Calgary’s mayor is known for his social media savvy and couldn’t resist a selfie with Canada’s oldest and youngest mayors.“Our last conversation with Hazel about how to approach the next federal election. You sound like you’ll miss Hazel! I will,” said Nenshi. “I don’t have to tell anyone in Ontario how remarkable she is.”Nenshi says the federal election next year should be about nothing but communities. “Now it’s up to the parties to say what they’ll do so I’m interested in what Trudeau has to say,” he said.Trudeau began his speech talking about transit. “You can’t move ahead on transit without help from other levels of government, so that’s why we’d have a national transit strategy,” said the federal Liberal leader.Nenshi tweeted he was most surprised that Trudeau started his speech by saying the Conservatives did something right. “It was good to index the gas tax but they didn’t go far enough,” said Nenshi via Twitter.