Well worth a visit if you are in Valencia is the area just to the south of the city known as Albufera.
Albufera is a large freshwater lagoon separated from the Med by just a couple of sand dunes. It has been designated as an important wetland area and provides sanctuary for millions of wetland birds on their migratory routes to Africa. Being a bird person I was a little disappointed not to see more exciting/exotic birds then the mallards and herons that abounded. However it was still delightful to see them and I wonder if a trip during the breeding season in spring might not be a better time to visit if bird life is what you are after.
Very easy to get to by the frequently running number 25 bus from Colon for €1.50 per single ticket, it takes 30-45 mins and you can even take your bike on the bus if you want to experience the nature reserves and various cycle routes.
If you get off the bus at Gola de Puchol, you will see the gaggle of boatmen on a jetty waiting to take visitors out on the lake for a 35 min tour for €4. Apparently the sunsets over the lake are particularly lovely and we are definitely planning on going back to do this next time, who doesn’t love a sunset crusie? The towns in this area El Saler, El perellonet and El Palmer are worth a visit too either for the beaches or to sample the region speciality dish, paella! During the summer the many campsites along this stretch play host to the throngs of holiday makers seeking relief from the heat of the city so I imagine it gets quite busy. We went in October when the weather was perfect and it was all very quiet.
Overall a very pleasant day trip for the cost and effort