As Cairns is billed as the gateway to the Great Barrier Reef, there are TONS of diving and snorkeling options out there. My best advice is that you really do your research and ask lots of details about what is included before you make your booking, ensuring you really get what you want. We learned the hard way that not all diving experiences are created equally.
After doing some research both online and on travel books, we booked a 3 night live onboard through Coral Expeditions. It was advertised as a cruise with "plenty of diving opportunities" and since it was live onboard, you could go to less visited places of the reef. All the expenses were included, so we thought it was a great deal. What they failed to tell us is that this is really NOT a diving-oriented cruise, but more of a cruise with MAYBE some diving included. When we got onboard, it was obvious that it is geared towards an older crowd (at least 60-70s, while my travel parter and I were the only 2 people in our 30s). Mind you, I have no problem traveling with an older crowd. However, when we asked the staff we were informed that our diving would most likely be very limited as the activities were tailored to the group and this group was not diving. We were shocked to find out that there would only be 2 potential dives in almost 4 days of cruising!!!! After much talking to the dive master and trying to see if they could provide us with what was really advertised, we got nowhere. They were very apologetic, but could not provide more diving time considering it would be only 2 people. Needless to say that with only 6 days in Cairns, we opted to get off the boat and stay in the city. No, they have have not refunded our money even though we have been fighting with them and their misleading advertising. If you want to just cruise, this may be a good option, but definetly stay away if you want some good diving.
What we ended up doing instead is going on Several of the day trip diving boats. We bought a 3 day pass though the Quicksilver Group and had a great experience!!! They have a fleet of 7-8 boats sailing both out of Cairns and Port Douglas and you can sail on any of them each day, depending on what you want to do. They all go to different locations on the reef, and have different activities. You can do up to 3 dives per day and/or snorkeling, and the divers are grouped based on experience. Yes, it is a larger crowd, but you get a good deal for the money. I specially liked the Poseidon...their crew was AMAZING!!! We fought really windy conditions and everyone was sea sick when we first sailed (and I do mean everyone!!!). They took great care of us and made sure everyone was as comfortable as possible under the circumstances. They really took safety seriously out on the dives and were readily available to help anyone in trouble. I would highly recommend them.
Overall, we made the best of our time out there and were able to enjoy the Reef, which was the main goal of our trip. My recommendation is that you really are careful about what you book, and ask a lot of questions. There really are a lot of companies out there, ans you don't want to pay for something and find out it's not at all what you expected!!
Going on a 3d/2n liveaboard trip out at Great Barrier Reef is the way to go. You'd have around 10 dives including 2 night dives. It's also not just limited to scuba divers, snorkelers can also join the trip. A tip when booking your trip, the liveaboard price is cheaper if you book it in Cairns. Just have a walk around town. The price is around $50-100 cheaper than booking online or with any travel agent.
Cairns Situated In the North eastern region of Australia and Is the Gateway to the Barrier reef, So if You like to Dive or to see the Reef why not take an Excursion with friends or family by boat about 1 hour promises truely Breathtaking Coral and colourful fish and Underwater Fauna.
If your Looking for a beach Cairns is a no no it is Mostly salt marsh, Yes and it does have a lot of salt water crocs so becareful when walking on the outskirts of the city at Night.
Having said that the fireflys are very Wonderful to see.
If You Like Opals Why Not by Her a Ring or pendant Lots of tax free Shops in the city.
I got PADI certified through Down Under Dive. It cost app. US$250. This included 2 days of pool excercises along with classroom lecture/exams. Then you get 2 days out on the reef to do your open water certification dives and look around. In between diving you can snorkel around which I recommend, the reef is just as amazing at the surface as it is down under. They also gave me a free day out on the reef to dive and snorkel but I got sick and couldn't use it.
You can sign up for one of many daily cruises to the Great Barrier Reef for a day of snorkelling and scuba diving. The water is so clear and the clarity is good, you can see the bright colours of the reefs and fishes like an aquarium. If you don't have a scuba diving license, you can opt for an introductory 1/2 hr or 1 hr scuba diving session led by experienced dive master. They will literally drag everyone along in the waters, so it is pretty safe. This is my first experience with scuba diving, and I love every minute of it.
If you are in Cairns you must do a dive on the Great Barrier Reef. It's not the best diving in the world but not bad.
I went with a company called Cairns Reef Dive who I was very impressed with. The boat was good as were the dive guides on board. Lunch was tasty and they provided fresh fruit on the way back which tastes great after breathing compressed air for an hour and a half.