Costa Majahuas is the largest sub-region of Costalegre but perhaps the most desolate. It is quite flat with numerous large estuaries along the coastline that is made up of practically one long stretch of beach. It begins at Punta Las Penitas and continues southward to the San Nicholas River (also known as the Tomatlán River), where it borders the large estate/resort property of Las Alamandas. Along this coastline there is little to no development.
At the southern end is the new development of Xala, developed by the same group who developed the very prestigious La Mandarin situated north of Puerto Vallarta. Costalegre's new airport will be situated just behind the development. Xala is a large peninsula of land that has 8 km. of beach on its western border and a very large lagoon along its eastern length, 20 km. in total around its perimeter, totaling 1,268 hectares. The estuary actually meets the beach and is sometimes open to the open ocean. When fully developed Xala will consist of three boutique hotels, residences and condos with amenities such as spas, beach clubs, a hacienda, as well as an agricultural component. It is based around a “Hacienda Lifestyle by the Sea” with the master plan designed to incorporate the social and cultural elements of the region including a town “Pueblo” and an incorporated fisherman's village. Homesites are currently available for purchase and already a few homes are under construction.
Cajon de Peñas is a large fresh water reservoir situated further inland from Majahuas, where the development of Xeneques is situated. Xeneques is an ecological / touristic development strives to ensure the preservation of the environment for region.