On the Water
Fitzroy Island Resort's Dive & Adventure Centre rents out kayaks (single/double per hour $25/30), stand-up paddle boards (per hour $25), stinger suits and swimming vests for kids. The island transfer tickets offered by Raging Thunder (based in Cairns) include free use of its awesome ocean trampoline.
Glass-bottom boat tours (adult/child $30/15, 45 minutes) run at 10am and 3pm; book at the Dive & Adventure Centre. Day trips to the outer reef (adult/child $229/119, 45 minutes away) can also be booked here.
Scuba & Snorkelling
The Dive & Adventure Centre at Fitzroy Island Resort rents snorkelling gear ($20 per day). It offers free 10-minute introductory dives in the resort pool; intro dives in the sea are $115 ($80 for subsequent dives). Certified dives from the beach are $60; tank fills are $15.
The staff at the dive centre will let you know the best places for snorkelling; the rocks off Nudey Beach are one of the most popular spots. Take extra care not to step on or break off any coral.
There are four marked tracks running through and around the island. The Secret Garden Walk (1km return) is a leisurely stroll through the rainforest that returns via the same path; the easy trek to Nudey Beach runs a similar length. For something more challenging, take the steep Lighthouse Track (3.6km), which climbs up to what was the last-staffed lighthouse in Australia, or try the Summit Circuit, a 4.2km (2½ hours return) hike through the forest up to a 270m peak, offering superb views. Take plenty of water, sunscreen and bug repellent.