We recently spent 2 weeks camping at Sebastian Inlet Fl state park...The park is bounded on 3 sides by water, the Indian River Lagoon, the Inlet and the Atlantic. We stayed at the campground, there are no lodges in the park but the campground was very well maintained, clean bath houses., right on the inlet with some waterfront sites. The park has lots to do with a beach, hiking, fishing, wildlife viewing( many birds, dolphins and manatees could be seen from our waterfront site) surfing, a gentle shallow cove pond with a great sand bottom for children, a small but interesting fishing museum( free and not nearly as boring as it sounds) and a treasure museum ( $2)dealing with shipwreck treasure found right of fthe coast there.
Enjoyed an inexpensive boat ride past Pelican Island National Wildlife Refuge( Environmental Learning Center, Vero Beach Fl, $14 for a 90 ish min. ride on a pontoon boat with a naturalist) and one on the south prong of the Sebastian river( not as much wildlife but beautiful scenery, same info as the first)
Food is a little far away, breakfast not a problem with Long Point state park restaurant about a mile down A1a ( great food) but they are only open for dinner on Fri and Sat( might open for more nights) and it is about 1/2 an hr to get most other places. ( will review a few )
Also within an hrs drive I'd recommend the Merritt Island Black Point Drive about 40 mins. north of Sebastian at Titusville ( free) , McKee Garden( under $10 charge unless you belong to another reciprocating garden)in Vero Beach and a wonderful Smithsonian exhibit in Fort Pierce of the ocean and local sealife with enthusiastic guides( free on Tues.)