I will be staying in the Flamingo Beach area for most of the week I want to add one more destination that will have wildlife, tropical forest and hiking. I thought I had decided on MA until I read more of these great posts. Would Arenal area be more of what I want? How from Flamingo to MA? to Arenal?

Since you're already having beach time, Arenal would be a nice complement. We loved Arenal. You could do the Cano Negro tour to see wildlife, hike at the Hanging Bridges, watch the volcano flow, and go to the natural hot springs like Tabacon and Eco Termales. That would be my vote. Or if you want to do something really different, the Osa is great for wildlife, tropical forest, and hiking.

Have to agree w/volcanogirl and also recommend Arenal. We had more fun there then any other place we have been in CR, especially over MA, which to me was to touristy and not what I expected. In Arenal and the surrounding area, you have incredible waterfalls, Rio Celeste, La Fortuna, the hot springs, and all of the hiking you could ever want, and most of all, when you are right next to an active volcano, sitting down to an incredible meal, and you can see the lava flowing down the side of the mountain, it is magical. Either way, enjoy.

Totally agree west; we had a strong connection to Arenal and just loved it; MA I can take or leave, but I think families with young kids enjoy it because it's so easy to get around and has all the restaurants, etc. I would pick Arenal every time especially if you're getting beach time somewhere else.

I think VG and ewesthoff have given you terrific advice. I personally enjoyed MA and we did see lots of wildlife there, but since you'll get some good beach time in at Flamingo, I think Arenal would give you the best variety for your trip.

The Cano Negro tour should get you some good wildlife sightings. We even saw coatis and tayras on the grounds of our hotel in Arenal.

I think Arenal will nicely compliment your time in Flamingo.