Water Sports
The main water sport around this island would be sailing. Because the main island is very wealthy it is the playground for those that have a lot of money which means some impressive sailing craft out on the water. A yearly race draws the crowds to the area and one can easily find a place to rent a boat for the day to enjoy the wonderful surf. Swimming is great around the island as well and there are many white sandy beaches. The largest portion of the population heads to the beach on the weekends so it is best to hit the surf during the week to avoid the crowd.
Island Diversity
Because the island is large the culture is rather diverse. The Romans and the Greeks left behind parts of themselves on the island and the populations of both are still present. Most often you will find the French on the island and the native tongue is French with a bit of English and Italian thrown in for good measure. English is spoken to cater to the tourist trade for the most part and it may be difficult to find someone who understands you if you are from the US.
Activities
Many of the activities on Porquerolles are related to the vineyards and wineries around the island. One can take a tour of the vineyards which ends with a wine tasting session that is rather impressive. The botanical gardens are also a site to see. The gardens span for miles and contain some of the most rare plants and trees on the planet. Crafts from the locals are made right before your eyes and hiking and cycling are very popular as well.