Portland’s Old Port Festival turns 40 this year, which means the hangover’s gonna be twice as hard to recover from than when it was half as old. The parade starts at the top of Exchange Street at 11 a.m., and from there it’s all music, dance, kids’ stuff, unhealthy (read: delicious) food and vendors galore. Musical highlights include performances by singer-songwriter Amy Allen, Irish punks The Pubcrawlers and Scottish punks Enter the Haggis. It’s free. portlandmaine.com.

