The Nueva Umbría path is a linear route that runs through the Catalán marshes and brings the visitor closer to the source of the Flecha del Rompido, a row of dunes running parallel to the coastline that has been formed by the deposit of sand from the tidal dynamics and the contributions from the mouth of the Piedras river.

The Catalán marshes are part of the complex of the Piedras river marshes and its tributaries. It is the marsh that is formed around the Arroyo del Fraile and the Caño de la Vera, practically at the mouth of the Piedras river. The hiking trail begins at the intersection of the Camino de Nueva Umbría track with the road from La Antilla to Terrón. The route follows a fairly straight line on a tarmacked road. It is a section used by road traffic.

During the first part of the itinerary, the visitor enjoys wide views on both sides of the marsh as well as the Torre Almenara del Catalán located on the cliff that rises above the La Antilla campsite. The Tower is an old defensive structure from the 16th century whose purpose was to monitor the coast against possible incursions by Berber pirates. On the other side of Piedras river lies the tourist complex of El Rompido, as well as the aquaculture farms of El Lancón.

The path runs overtop of the marsh complex where, when the tide is low, it is very common to see numerous crustaceans that serve as food for seagulls and other birds in the area. The vegetation here has halophyte characteristics and is limited to the highest lands made up of more consolidated materials.

After crossing the bridge over the Arroyo del Fraile stream and travelling a short distance over the southern end of the marsh, the trail enters an area of sands and dunes. Right at this point the old Nueva Umbría path ends and the rest of the route runs over a wooden walkway that runs over the succession of dunes that constitute the beginning of the Flecha. The vegetation adapts to the new environment and is now dominated by white broom, sea thistle and the marram grass and serves as a shelter for the common chameleon, an emblematic species of the Marismas del Río Piedras y Flecha del Rompido Natural Park.