While many local airlines do fly from both San Juan and Fajardo to Vieques, we chose the slightly longer and much cheaper option of riding the ferry across the ten miles separating Puerto Rico and its tiny island province. This ferry leaves from the Fajardo Ferry terminal (from which ferries to Culebra, another island off the Puerto Rican coast, also leave) and costs a grand total of $4 for a round trip ticket.
The ferry ride took about an hour. There were two floors to the boat, and the upper was mostly covered but was still outdoors. I don’t do well indoors on rocking boats, so I chose the top, along with nearly everyone else in our group. None of us really minded the ride over, since none of us got seasick and all of us enjoyed the nice view of brilliant blue water and the cloudy visage of Puerto Rico on the horizon. We even got to see a sinking boat in Fajardo Harbour, although we’re not sure whether its owner knew it was sinking or not!
On the way back, we took the 6:30am ferry so we could spend the rest of the day visiting El Yunque and Luquillo. Obviously, not many people were awake for this ride, but I did my best to stay awake to see the sun rise over Vieques. Unfortunately, the seat I picked—which had promised the best pictures, being the last one on the boat—was also the only totally uncovered seat. This would have been fine except for the rain and the torrents falling off of the roof, straight onto me. I stayed there just long enough to watch the sky light up in pinks and oranges as the sun slowly pulled itself up over the horizon and then found a much drier seat in which to sleep for the rest of the way!
There are many ferries—both passenger and cargo—to and from Vieques throughout the day. Passenger ferries leave Vieques for Fajardo at 6:30am and 11am daily, 3pm Monday through Friday, and 1pm and 4:30pm on Saturdays, Sundays, and public holidays. Passenger ferries going in the opposite direction—Fajardo to Vieques (arriving at Isabel Segunda township on the island)—leave at 9am daily, 1pm and 4:30pm Monday through Friday, and 3pm and 6pm on Saturdays, Sundays, and public holidays. The cargo ferry only runs Monday through Friday and costs more than $4 depending on the size of your vehicle. I recommend that if you do not have a 4wd, which we did not, to just take the passenger ferry and either rent a jeep-type vehicle or use taxis while on the island. This is because many places on Vieques are only accessible on small dirt roads, which you may not be able to navigate with a non-4wd. Also, rental car companies tend to be very picky about what type of roads your car is driven on. However, if you do plan on taking a car across to the island, the cargo ferry runs from Vieques-Fajardo at 6am, 1:30pm, and 6:30pm, and runs from Fajardo-Vieques at 3:30am, 9am, and 4pm.