Hi Maddy,
I know there is an intermittent ferry between Puerto Barrios and Punta Gorda, but this is not much help for you.
Considering the size of your group, I am sure it would be much more economic to charter a vessel to take you from Puerto Cortez to Punta Gorda. Here is some info on the Puerto Cortez/Placencia ferry. I'm sure they can either charter a boat for you, or drop off your group at Punta Gorda on the way to Placencia
This could have changed, but it looks pretty convincing.
http://www.placencia.com/Informative%20_%2...elize.htm#WATERTHE EXPRESS WATER TAXI: (Tickets available at the Placencia Tourism Center)
Departs Placencia Fridays - 9:30 a.m. Arrives Big Creek 10 a.m. Departs - 11:00 a.m.
Arrives Puerto Cortez, Honduras, 2 p.m. at Laguna.
Departs Puerto Cortez , Honduras Mondays - 10 a.m. Arrives Big Creek 12 noon. Departs - 1:30 p.m.
Arrives Placencia 2 p.m.
Tel: 202-4506 or 523-4045.
If you need more assistance, try this - Lan Sluder knows everything there is to know about Belize, and how to get there.
Free Answers to Any Question About Belize! Get any question about Belize answered by an expert ... free. Lan "The-Belize-Answer-Man" Sluder is editor of Belize First Magazine and the author of several books on Belize, including San Pedro Cool, Belize First Guide to Mainland Belize, Adapter Kit: Belize and Living Abroad in Belize. His new guidebook, Fodor's Belize 2008, is now in bookstores worldwide. If he can't answer your question, he'll find someone who can.
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