Hello,
I am going to Manuel Antonio next month and we don't have much planned for our 4 night stay. We are White Water rafting and Ziplining in Arenal already.
Would it be worth going north and catching a fairy to the peninsula? We don't have a car... Is this really possible without getting a private van?
Are there any other recommendations for a day trip away from Manuel Antonio?
Your help is much appreciated!

You could take the bus to Golfito and then take the ferry to Puerto Jimenez on the Osa Peninsula. Or you could take the bus to Puntarenas and then take the ferry across to Paquera and then the bus to Montezuma.

Neither one of these are day trips.

www.thebusschedule.com
www.yourtravelmap.com

A good day trip I think would be heading down to Uvita/Dominical area, although I'm not familiar with the shuttles/transport to and from MA. It's a beautiful area to visit and not too far from MA. Horseback to Nayuca Waterfalls or hike through Hacienda Baru, visit beaches, wander around...

I like the idea of going to Dominical! Now I just need to find out how to get there! Thanks for the ideas!

You can get there via bus (see link above) or check the Interbus schedule if you're going to do more than a day trip (usually only a morning departure so you'd have to spend the night).