Castillo Marathon 2026: route and elevation

Plan your race pace

Maratón del Castillo links Plaza de Castilla in Madrid with Manzanares el Real through livestock tracks, dirt roads and trails in the Cuenca Alta del Manzanares area. Its 42 kilometers and 830 meters of positive elevation make it much closer to a demanding trail race than to a conventional road marathon.

The 2026 edition is listed for Sept. 19 in the Community of Madrid, with a planned 8:30 a.m. start and individual participation. The available technical information from the previous edition shows the nature of the course: it crosses Fuencarral, Tres Cantos and Colmenar Viejo before reaching the Mendoza Castle and the landscape around the Santillana reservoir. The strongest reference for preparing the distance is a time limit of eight hours and a clearly rolling profile.

The race is part of the Madrid-Segovia program and shares the linear adventure character of other events organized alongside it. Start and finish are in different municipalities, so transportation, bag handling and post-race logistics matter almost as much as pace selection. General information is available through the popular race calendar and the race map.

A trail marathon between the city and the mountains

The main appeal of this race is its gradual change of scenery. The opening kilometers leave an urban setting, with streets and crossings near major infrastructure, but the landscape changes as the course moves north. Runners leave Madrid’s density behind and enter a succession of service roads, tracks, dirt roads and trails leading toward the mountains.

The route follows sections associated with livestock tracks and the Madrid branch of the Camino de Santiago. It is not a mountain course from the very first meter: it combines urban outskirts, historic paths and protected natural spaces. That mix gives the race its identity. Asphalt helps runners gain speed in some sections, while dirt and trails require careful footing, especially where roots, loose stones or changes in gradient appear.

The Cuenca Alta del Manzanares Regional Park contains much of the race’s landscape value. La Pedriza, the Santillana reservoir and the proximity of Manzanares el Real Castle form an unusual backdrop for an event that starts in the capital’s wider urban area. The finish is not merely a kilometer marker but the visual ending of a journey from Madrid into the mountains.

Technical profile and changing terrain

The reference distance is 42 kilometers, although the technical documentation has also described the course as approximately 41.9 kilometers, with occasional route changes. Positive elevation is listed at 830 meters and negative elevation at 650 meters. The difference between those figures shows a course with an overall upward tendency, but not one continuous climb: the profile alternates between short climbs, descents and relatively fast sections.

The surface is mixed. The organizer’s technical sheet indicates 54% dirt track, 20% trail and 26% asphalt. Another course description emphasizes that the route mainly uses tracks and natural paths. Both references agree on the essential point: the surface does not allow the event to be approached like a road marathon, even though it includes asphalt kilometers and urban areas.

The opening may be misleading. Madrid streets and the first tracks can allow a smooth rhythm, but accumulated effort becomes more evident near Colmenar Viejo and around the medieval Batán Bridge. The final kilometers near Manzanares el Real combine fatigue, remaining elevation and constant attention to the ground. The approach to the castle creates a recognizable finish, but it does not remove the difficulty of the preceding kilometers.

The route through Madrid, Tres Cantos and Colmenar Viejo

The start for the reference edition is located on Agustín de Foxá Street, beside Plaza de Castilla. From there, the route follows Mauricio Legendre, Llano Castellano and several streets in the Fuencarral area. The passage through Alamedillas Park and the pedestrian crossing over the Colmenar road mark the transition between the urban fabric and the peripheral tracks.

Around kilometer 5.7, the course reaches Fuencarral Cemetery. Shortly afterward, it uses a livestock track to cross the railway and the M-40 through an underpass. The route continues beside the El Pardo wall and along the old road from El Pardo to Colmenar. The elevated crossing over the Cercanías and AVE railway lines near kilometer 9.7 is another distinctive point before the course reaches El Goloso station and the cycle path leading toward Tres Cantos.

Tres Cantos appears at approximately kilometer 15.8. From that point, the landscape opens up and the course feels less urban. The entry into Colmenar Viejo takes place near kilometer 25.5, along the cemetery road and beside Santa Ana Hermitage. La Magdalena promenade, the park, Paseo del Redondillo and Avenida de los Poetas form part of an urban transition toward the paths of the final third.

The decisive kilometers toward the castle

After Colmenar Viejo, the course takes the lower Cerceda road and heads toward the medieval Batán Bridge, located around kilometer 33.8 according to the available description. This section has both sporting and heritage value. It also requires attention to organizer updates, because railway expansion works forced changes to the traditional route in a previous edition and added approximately 400 meters.

The approach to Manzanares el Real includes the tail of the Santillana reservoir and entry through Calle de la Paz. The route crosses the M-608 road, continues along Peña Sacra Way and passes in front of Mendoza Castle. The finish is located in the Manzanares el Real area, close to the entrance to the Sierra de Guadarrama National Park.

In this final section, running by feel may be more useful than chasing a rigid target pace. Accumulated elevation, changing surfaces and the distance already covered naturally affect speed. Saving energy from the start is a performance decision, not a sign of weakness: an overly fast opening can turn the final trails into a long walk.

Mandatory equipment and self-sufficiency

The technical information for the reference edition requires a headlamp or flashlight at the start, a water reservoir with a minimum capacity of one liter, a reusable cup or bottle, a mobile phone with a charged battery, at least 10 euros, warm clothing and personal equipment for carrying waste. The drinking system is especially important because cups and bottles are not provided at aid stations.

The requirement to carry a personal container changes hydration strategy. It is not enough to rely on an aid station providing a cup: every participant must be able to drink and refill a cup or bottle at designated points and at the springs listed in the roadbook. In a race that can last up to eight hours, water management is a safety issue, not merely a matter of convenience.

Wrappers from gels, bars and other products must be marked with the bib number, according to the race conditions. The measure is intended to control waste in a sensitive natural environment. Failure to carry mandatory equipment can lead to a penalty of at least 30 minutes, loss of eligibility for trophies or disqualification, depending on the violation. Throwing waste, leaving the route, missing a checkpoint or ignoring staff instructions can also lead to exclusion.

The headlamp has a practical purpose even though the listed 2026 start is later than the 2025 start. Light conditions can change with the season, weather and final organizational decisions. The definitive reference must always be the regulations and roadbook for the relevant edition, especially if works, diversions or checkpoint changes are announced.

Aid stations, time limit and services

The available technical information counts three liquid aid stations and two solid aid stations. It does not specify the exact products at each point, so the official documentation should be checked before deciding how much food to carry. In a course like this, aid stations help with replenishment but do not entirely replace a personal hydration and fueling strategy.

The maximum time indicated by the organizer is eight hours. That gives runners who walk climbs or alternate running and hiking a reasonable margin, although the time plan must include checkpoints and pauses. A seven-hour limit appears in one external listing and does not match the more recent technical information from the reference edition; eight hours is therefore the safer figure until an update is published.

The race includes chip timing, a bag drop, showers, food or sandwiches at the finish, a finisher diploma, trophies for winners and a prize draw, according to the consulted information. Participants’ bags are transported to Manzanares el Real using a specific identification tag handed out during bib collection.

Showers are located in the changing rooms at Las Ermitas municipal football field on Calle Cañada, approximately one kilometer from the finish. This distance should be considered when planning the finish, particularly if the runner arrives tired, cold or with muscle discomfort. The finish, bag collection and changing rooms are not all in one compact location.

How difficult is it for a road runner?

The distance may feel familiar to anyone who has completed a road marathon, but the bib number does not tell the whole story. A 42-kilometer trail marathon requires changes in stride, looking several meters ahead and accepting that kilometer pace will not remain constant. Climbs are handled with shorter steps and descents require control, not simply speed.

The 54% of dirt track provides sections where a steady rhythm is possible, but the 20% of trail can interrupt cadence. Urban asphalt is not always an advantage either: after many hours, the hard surface can overload the calves, soleus and quadriceps. The difficulty comes from the combination of surfaces and elevation, not from one extreme section.

For a road runner, general preparation should include hilly routes and sessions on uneven ground. There is no need to make every workout a mountain outing; the aim is to accustom the ankles, muscles and perception of effort to changes that do not appear on a flat avenue. It is also useful to test shoes, pack, hydration container and race nutrition in advance.

Weather can transform the course. In September, exposed areas may still be warm while early morning or mountain sections can feel cooler. The mandatory warm clothing reflects that variability. A clear morning does not guarantee that the entire day will keep the same temperature or that wind will be irrelevant in open areas.

Registration, dates and details requiring confirmation

The reference sheet for 2025 listed a starting price of 45 euros. No definitive 2026 fee appears in the available information, so it cannot be assumed that the same amount remains valid. The consulted data also do not state a participant limit, registration closing date or unequivocal official URL for the 2026 edition.

Different listings date the 2025 edition on Sept. 20 and 21, while the 2026 reference places the event on Sept. 19 and gives an 8:30 a.m. start. The discrepancy shows why a historical record must be distinguished from the active event listing. The final date, time and course must be checked in the regulations for the current edition, rather than inferred from the previous year’s data.

It is also important to distinguish the sporting description from administrative classification. Some external pages describe it as a trail marathon, others as a 42-kilometer event within Madrid-Segovia, and one listing links it to a 50K UTMB Index category. These labels do not change the announced distance, but they may affect how difficulty, certification or event ranking are interpreted.

The 2026 listing indicates that the race is intended for adults. Information about certification is not consistent either: the 2025 sheet states that the distance was not certified. It should therefore not be presented as a certified road marathon or compared without context with an officially measured urban event designed for a personal best.

A finish defined by heritage and landscape

Mendoza Castle gives the race its name and provides a recognizable final image. The fortress, Santillana reservoir and the nearby La Pedriza create a scene unlike the start, surrounded by towers and urban traffic in Plaza de Castilla. The contrast works as a geographical narrative: the race leaves Madrid, crosses metropolitan corridors and ends beside a historic landmark with a strong visual presence.

This heritage value is not separate from the sport. The course uses old roads, livestock tracks and passages connecting towns and natural areas. Each change of scenery helps measure distance in a less abstract way than a watch: Fuencarral, Tres Cantos, Colmenar Viejo, the medieval bridge and Manzanares el Real act as chapters in a long route.

Maratón del Castillo therefore occupies a distinctive place in Madrid’s race calendar. It does not offer the regularity of an urban race or the constant altitude of a high-mountain ultra. Its personality lies in transition and variety, in starting among the towers of Plaza de Castilla and finishing with the castle and mountains ahead. For runners seeking a marathon distance with an adventurous setting, the course offers a complete challenge while remaining closely tied to the history and landscape of the Community of Madrid.

The available information establishes its essential characteristics but leaves some 2026 details pending confirmation: entry fee, final regulations, exact aid-station locations, possible diversions and final bib-collection arrangements. That caution is part of responsible preparation. In a point-to-point event, a small logistical change can affect transport, arrival time and equipment management.

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