Lake Arenal and Bahia Salinas, in Northern Guanacaste are among the best Windsurfing destinations of the world, Constant and strong winds create this unique environment. Additional to this, you must add the natural surrounding, great landscapes and beautiful and nice charming people that will make your stay unforgettable.

Windusrfing Costa Rica by Hotel Tilawa has some useful information.
Legendary board shaper and RealWind Founders Rob and Laury Wymore enjoying a session at Lake Arenal, Costa Rica, January 2005 with 35 knot winds and balmy 75 degree water.
Costa Rica windsurfing is at it's finest on Lake Arenal in Costa Rica. The Tilawa Windsurf and Water Sports Center is open year round providing windsurfers and other sport enthusiasts a comfortable home for Costa Rica windsurfing adventures. Hotel Tilawa guests receive discounts on RealWind board and sail rentals. See our RealDeal Special.
Tilawa Windsurf center on Lake Arenal, Costa Rica, has been open year round since 1993. We offer a complete new line of 2004 RealWind boards and sails for the finest in windsurf fun on high winds and lake chop conditions. Windsurf Lessons are offered for the beginners to advanced students.
Lake Arenal Costa Rica has warm waters, strong and steady seasonal winds, and a unique country style not easily matched by other world class windsurf locations. Hotel Tilawa, just a few minutes from the Tilawa Windsurf Center offers large comfortable rooms, hot springs jacuzi, swimming pool, tennis, epicurean cuisine and a great place to hang out on Lake Arenal Costa Rica between windsurfing sessions.