Has everything, 100's maybe 1000's of boulder problems all within a few minute walk of the camp ground. Several sport climbing areas (some close, some you'll need a car for), and more cracks than you can climb in a life-time.
Lakes to swim in, ocean, mountains to hike, amazing mountain bike trails, the list goes on. The town doesn't promote itself as the outdoor recreation capital of Canada for no reason. You can also get to Whistler in an hour if you want to spend $$ and check out a tourist trap/town. Vancouver is 45 minutes in the other direction and has everything.
Downside - August is BUSY. September is the beginning of the real climbing season as the crowds start to diminish. Best way to avoid the crowds; take the weekends off or spend them at more distant remote crags, and avoid using the Squamish Select guide book (this book is actually quite good, but everyone has it so they all end up at the same 5-star climbs). August can also be pretty hot. But, because it's next to the ocean, and there is also always a breeze/windy, the boulders in the forest are a great place to go.