My bf is leaving for Ottawa on Wed....for almost two months. He's been there before in the dead of winter, but now that the weather will be much warmer, he's looking for ideas on things to do on his days off or any other free time that he (hopefully) will have. I hear there's a tulip festival or something that'll be happening....but are there any must-see places, events, tips, etc. that you can think of?

Thank in advance for any input!