Picnic, anyone? In Madrid you can picnic most of the year, if you pick your day and your place. Below is a list of picnic sites, updated to show where you can go even in fall or (gasp) winter.
To decide where to have your picnic, different factors come into play. What is your time frame? How big is your group? How mobile is your group, ie do you need a place with table-side car access, or can you walk a bit? Do you have a car, and do you want to use it? How much infrastructure do you need, tables, barbecue facilities, bathrooms, water, or just a shady place under some trees? Do you want to dabble your feet in a stream?
In the city:
If you’re short on time and want good infrastructure, the more urbanized parks like the Retiro, Parque del Oeste or Tierno Galván may be your best bet, though not all have picnic tables and you will definitely be sharing space with a lot of other people. These parks are wonderful for a fast lunch with a bit of green, but probably not for a real spread.
If you want something nearby but a little wilder, head for the Casa de Campo. For best access (even by metro or bus) and best infrastructure, try the area around the lake, tennis courts and a little to the west following Paseo de los Castaños, one of the paved roads that leads away from the lake (remember most of the park roads are not open to cars on the weekend). This part of the park does have a fair number of people, so it may be difficult to find a table.
Another place in the Casa de Campo with infrastructure and good access for cars is the entrance from the M503, with a pine grove with tables, outdoor café and a big playground for kids. With less infrastructure and requiring a 10-minute walk: Puente de la Culebra. You can access this area from the southwest corner of the zoo: look for paved road following small stream upstream, away from zoo (watch the bridges, you’ll know when you find “Snake Bridge”). Also can access from lower end of Somosaguas neighborhood, gate in park’s back wall. Puente de la Culebra is one of the shadiest and coolest places in the park, though if group is large a quick scouting trip would be a good idea, to see exact placement and number of picnic tables.
If you’re up for a longer walk, the area called “Cuatro Caminos”, just south of Cerro Garabitas, has a water source and lots of picnic tables. This area is right by the bike track. The closest access by car is the parking lot at the bottom of the paved road that runs from near Puente de los Franceses along the base of Garabitas up to Cuatro Caminos: road is closed to traffic after the parking lot.
No picnics in some parks! Note that some city parks do not allow picnics, most notably El Capricho but also technically La Quinta de los Molinos and probably the secret gardens seen on some of the city walks. You might not have issues with park guards but I have heard that they’re quite strict in El Capricho.
Outside the city:
Puerto de Canencia: OFTEN HAS SNOW IN THE WINTER MONTHS. This pass is one of the prettiest in Madrid, and a good starting point for several easy to moderate walks. Drive north on M607 to Tres Cantos and Colmenar Viejo, turn onto M609 north of Colmenar, marked Soto el Real and Miraflores de la Sierra. Once in Miraflores de la Sierra take the right-hand road to Canencia after a sharp left curve. Just after highest point of the pass there is an unpaved turnoff to the right for a parking area. Do NOT park on the highway as the Guardia Civil occasionally patrols this pass and fines are stiff. Picnic tables around the parking area, though not many are shady. Water source on other side of highway at the beginning of a dirt road, there may be some shadier picnic tables by this “fuente”, but this area is closer to the highway. Check around parking lot for another water source (think there is one but I always use the one mentioned).
La Pedriza: North on M607 to Tres Cantos and Colmenar Viejo, turn onto M609 at north end of Colmenar, marked Soto el Real and Miraflores de la Sierra. About 6 kms from that intersection, turn left on M862 to town of Manzanares el Real, next to La Pedriza (the rocky area behind the town). This is one of the most popular summer picnic places near Madrid: a young Manzanares river, shade and LOTS of people!
Most people want to go to Canto Cochino (access beyond town, turnoff to the right from the M608, marked Centro Interpretacion Parque Cuenca Alta del Rio Manzanares or some variation of that) BUT access to Canto Cochino is limited to a certain number of cars, so you may have to wait to get in, even the fall or spring. Once there, the scenery is great but infrastructure is practically zero – this is done on purpose to discourage masses of people in a fragile ecosystem like La Pedriza. So go early, go on an off day or off season – La Pedriza is worth a visit, including the visitor’s center which is right by the barrier on the access road to Canto Cochino.
If you simply must go to this area on a summer Sunday, or if you got up late and prefer not to wait in a line of cars to get into Canto Cochino, you have some other options. Go to El Tranco instead of Canto Cochino, it is a little closer to town, has a little more infrastructure and no control for number of cars (parking can be a problem). Go to one of the nearby picnic areas that have been created to decongest Canto Cochino: one is on the M862 described above (turnoff to the right marked as recreation area) and the other is beyond town, turnoff to the left from the M608, past turnoff to Canto Cochino.
Boca Asno: MAY HAVE SOME SNOW IN WINTER MONTHS: A6 and M601 to Navacerrada pass, then down CL601 towards La Granja and Segovia. Once you’re past the famous Siete Revueltas curves and over the Eresma river, watch for signed access roads to the left. There are several turnoffs before reaching La Pradera, on the outskirts of Valsain and just a few kilometers from La Granja.This shady picnic area is along a pretty stream, with some infrastructure but not lots. As one of the best-know and nicest areas near Madrid it can get crowded, but it is fairly large so usually that isn’t a problem.
El Escorial: MAY HAVE SOME SNOW IN WINTER MONTHS: Look for the access to the Silla de Felipe II – on the M505 south of San Lorenzo de El Escorial monastery. There are lots of picnic tables in the oak grove around a little white chapel, or you can go up to the “Silla” lookout for a great view of the monastery.
South and west of Madrid: No mountains, but the rolling hills and rivers south and west of the city have a charm of their own, and in the cooler months this might be a better option for picnics than the mountains. There are equipped picnic areas in Ambite (almost directly east of Arganda , on the Tajuña river), in Chinchón (near the castle), and in Aranjuez. If you are willing to explore a little, Fuentidueña (where the NIII crosses the Tajo River) and Alcalá de Henares also have some good picnic places.