Ask most drivers what a triangular warning sign means and they’ll probably answer without thinking. Sharp bend. Roundabout ahead. Slippery road. But show them the P 35 sign, with its two cars and crossing arrows, and many are left scratching their heads.

That uncertainty is exactly why Spain’s Directorate General of Traffic (DGT) introduced it into the country’s official road sign catalogue. The sign warns drivers that they are about to enter a weaving lane, a stretch of road where vehicles joining a motorway and those preparing to leave it have to share the same space before going their separate ways. It might not sound particularly dramatic, but misunderstand the rules and the consequences can be expensive. Failing to respect priority can lead to a €200 fine and, in some cases, the loss of up to four points from your driving licence.

The layout itself is not new. Drivers have been using weaving lanes for years. What is new is the sign warning people that one is coming, and many motorists are only now discovering what it actually means.

The sign looks simple enough but it catches many drivers out

The first reaction many people have when they spot the P 35 sign is to assume it is another version of the familiar merging traffic warning.

It isn’t.

A weaving lane works differently because two manoeuvres happen at the same time.

One driver is trying to join the motorway while another is trying to leave it. For a short distance, both vehicles use the same lane before their paths separate.

If you’ve ever found yourself accelerating onto a motorway while another car suddenly moves across towards the exit you were aiming for, you’ve already experienced this situation.

The difference is that the P 35 sign tells you it is about to happen before you get there.

The DGT introduced the sign after updating Spain’s official vertical road sign catalogue in 2025. It normally appears between 150 and 500 metres before the weaving lane begins, giving drivers enough time to prepare.

Its design follows the standard warning format used throughout Spain.

It has a red border, a white background and two black cars connected by arrows that cross in the middle. The image is intended to show exactly what will happen ahead. Two streams of traffic will briefly overlap before separating again.

Once you understand the meaning, the sign is fairly straightforward.

The difficulty comes when drivers are unsure who should move first.

Who has priority? The answer is not always what drivers expect

This is where many motorists get caught out.

It is easy to assume that vehicles already travelling on the motorway always have priority. In most situations, that is true.

However, weaving lanes are governed by the normal priority rules set out in Spain’s General Traffic Regulations, and those rules depend on what each driver is doing.

A vehicle joining the motorway must normally give way to traffic already using it.

However, if a driver leaving the motorway has already started moving into the weaving lane, that vehicle takes priority over one that is still entering.

The DGT also offers practical advice rather than simply quoting the regulations.Drivers leaving the motorway are encouraged to ease off the accelerator slightly so they can move in behind the vehicle joining the road.

Meanwhile, motorists entering the motorway should build up speed positively, where conditions allow, so they can merge smoothly ahead instead of remaining alongside another vehicle.

Good timing often matters more than sudden braking.Using indicators correctly is equally important.

The signal should be activated before changing lanes, giving other drivers enough warning to react safely. Waiting until the manoeuvre has already started defeats the purpose.

Motorists travelling on the main carriageway also have a role to play.

Whenever traffic conditions allow, moving into the next lane can create valuable space for vehicles joining the motorway. If changing lanes is not possible, reducing speed slightly can make merging much easier and help avoid sharp braking.

A moment’s hesitation can quickly become an expensive mistake

The P 35 sign may be new, but the penalties for ignoring the rules are well established.

Drivers who fail to respect priority in a weaving lane can face a €200 fine, while more serious infringements may also lead to up to four penalty points being removed from their licence.

For many motorists, the greater risk is not the fine itself but simple confusion.

Road signs become so familiar over time that drivers often react automatically without really looking at them. A new sign breaks that habit.

That is exactly why the DGT believes the P 35 deserves attention.

Motorway traffic is already moving at high speed, leaving little time to make decisions. When several vehicles are trying to change lanes within a short distance, uncertainty can quickly turn into sudden braking, missed exits or near misses.

The sign is not asking drivers to learn a completely new rule.

Instead, it serves as an early reminder that the next section of road demands a little more attention than usual.

Spain’s road network continues to evolve, and the country’s road signs evolve with it. Even experienced motorists who have spent decades behind the wheel occasionally come across a symbol they have never seen before.

The P 35 is one of those signs.Learning what it means now is far easier than trying to work it out while travelling at motorway speed with cars joining from one side and leaving from the other. It could also save drivers from an avoidable fine and make one of the busiest parts of the motorway a little safer for everyone using it.

Thinking of driving across Spain this summer? You may want to check the calendar before you set off. Spain’s traffic authority, the DGT, has revealed the weekends when roads are expected to be at their busiest, with more than 100 million journeys forecast over the summer holiday season. Those dates will bring heavy traffic, more police patrols, extra speed cameras and a greater risk of accidents, making them the least favourable times to travel by car.

The warning comes as Operation Summer 2026 gets under way this weekend, with millions of people heading to the coast, the mountains and family homes across the country. If your travel dates are flexible, avoiding the busiest periods could mean a much smoother journey.

The four weekends expected to cause the biggest traffic jams in Spain

Every summer follows a familiar pattern. Schools finish, workers begin their annual leave and, almost overnight, Spain’s road network fills with holiday traffic.

This year is expected to be even busier than usual. According to figures released by the government, more than 100 million road journeys are expected during July and August alone.

Not every weekend will be equally busy, however.

The DGT has identified four periods when traffic is expected to reach its highest levels because they coincide with the start or end of the main holiday changeovers.

The dates are:

July 3, 4 and 5 for the First Summer Operation.

July 31, August 1 and August 2 for the Second Summer Operation.

August 14, 15 and 16 for the Third Summer Operation, which coincides with the Assumption holiday.

August 28, 29 and 31 for the Return Operation, when many holidaymakers travel home before the start of September.

If you are planning to drive on any of those weekends, expect queues on the main motorways leading to coastal areas, heavier traffic around tourist hotspots and longer journey times throughout much of the country.

For many families, those dates are unavoidable because they coincide with booked accommodation or annual leave. Even so, the DGT says knowing what to expect allows drivers to prepare properly and avoid unnecessary risks.

Why there will be more police, speed cameras and restrictions on Spain’s roads

The increased traffic is also the reason why drivers will notice a much stronger police presence over the coming weeks.

The Guardia Civil’s Traffic Division will deploy more officers across Spain, while the DGT will increase the number of mobile speed cameras and aerial surveillance to monitor traffic from above.

Several temporary traffic measures will also be introduced to help keep vehicles moving.

Where possible, additional lanes will be opened on busy routes. Roadworks on major roads will be suspended during the busiest periods and heavy goods vehicles will face restrictions on certain stretches of road where congestion is expected.

There is another important difference this year.

Instead of focusing only on the main departure weekends, the DGT has decided to extend these measures to almost every summer weekend.

The special traffic operation will also cover June 26 to 28, July 10 to 12, July 17 to 19, July 24 to 26, August 7 to 9, August 21 to 23 and September 4 to 6.

On those weekends, the enhanced measures will normally run from 1pm on Friday until midnight on Sunday, when traffic volumes tend to be at their highest.

The DGT says the strategy is based on previous experience. During Operation Summer 2025, fatal road deaths fell by six per cent compared with the previous year. Even so, there were still 228 fatal crashes, including 173 on conventional roads, which continue to account for the vast majority of deadly accidents.

The simple advice that could save you hours in traffic

One of the most practical recommendations from the DGT has nothing to do with speed or road rules. It is simply about choosing when to leave.

Based on its historical data, the authority advises motorists to avoid setting off between 1pm on Friday and midnight on Sunday, as this is both the busiest period for traffic and the time when the highest number of fatal accidents has traditionally been recorded.

If possible, travelling early in the morning or later in the evening is likely to mean quieter roads and shorter journey times.

The DGT also encourages drivers to spend a few minutes planning before they leave home. Checking traffic updates through the DGT 3.0 app or the authority’s interactive traffic map can help identify delays, accidents or roadworks before setting off.

Long journeys should include a break at least every two hours, particularly during hot weather, when tiredness can arrive sooner than many people expect. Families travelling with children are also encouraged to plan regular stops rather than trying to complete long distances in one go.

Before leaving, drivers should also carry out a basic inspection of their vehicle. Tyres should be checked for pressure and wear, fluid levels topped up where necessary and brakes, lights, battery and engine inspected to make sure everything is working properly.

Finally, motorists should make sure they have the legally required documentation with them, together with the mandatory emergency equipment, including the V16 emergency beacon.

With millions of vehicles expected to share Spain’s roads over the coming weeks, a little preparation before turning the key could make the journey considerably easier and, more importantly, much safer.