The vast expanse that locals call the Zona Norte (Northern Zone) packs in a larger variety of activities than any other part of the country. You'll find almost everything in this region that Costa Rica has to offer, except beaches, of course.
Spend any amount of time here and you can partake of—take a deep breath—horseback riding, canoeing, kayaking, rafting, rappelling, windsurfing, kitesurfing, wildlife-viewing, bird-watching, bungee jumping, shopping, cloud- and rain-forest hiking, swimming, hot-springs soaking, and volcano (albeit now dormant) viewing. The zip-line canopy tour deserves special mention. The activity was invented in Costa Rica and has spread to all corners of the planet, while zipping along cables from platform to platform high in the trees has become Costa Rica's signature adventure activity.
The myriad activities make this, and especially Monteverde, Costa Rica's most kid-friendly region. Young children will "ooh" (and "eeewwww") at various area animal exhibits devoted to bats, frogs, butterflies, hummingbirds, felines, and snakes. Guided nature hikes abound; shorter treks can be entertaining and cater to younger ones' shorter attention spans. Most sure-footed and confident teenagers can participate in adult activities such as white-water rafting and canopy tours.
A few operators around here will tell you that kids older than eight can participate in canopy tours. Even if their brochures show children happily zipping from platform to platform, the gondola-like trams (Monteverde) are far safer ways for preteens to see the rain-forest canopy.
Most of the activities go on rain or shine, so don't feel you have to avoid a rainy-season visit here. During the wet months, it's almost a given that you'll get a bit damp on your canopy tour, hike, or horseback ride, and most tour operators provide ponchos. But to avoid a thorough soaking, plan activities for the morning. Rains usually begin around 2 pm, like clockwork, from July through December, although they can be more prolonged in September and October. The clearest time of day is normally before 8 am.