The GR10 is a hiking trail from coast to coast through the Pyrenees in southern France. You can walk smaller sections of the trail in one of the national parks. Or in about 50 to 60 days, you can walk all along the trail from the Atlantic Ocean to the Mediterranean Sea, 900km/560miles. This trail will lead you through gorgeous mountains and beautiful nature. From the warm beach of Hendaye to the perma-snow in Gavarnie, the GR10 trail offers varied landscapes and is suitable for hikers of all skill levels, making it certainly one of the best hiking trails in Europe.
On a scale from 1 to 10, hiking the GR10 is as difficult as you want to make it. Some people hike the GR10 in under 30 days, by walking about 7 hours per day on average. But of course, many people would prefer having the time to smell the wild flowers, or swim in the icy, glacial lakes. There is no need to make it a competition.
If you plan beforehand what sections of the GR10 you want to hike and in what time frame, then the GR10 won't be too challenging.
Hiking the GR10 is a serious undertaking, especially if you hike longer stretches. The GR10 is a great way to challenge and train yourself both physically and mentally, especially when hiking alone. The GR10 can also be a wonderful way to connect with your partner or family and spend many hours with them on the trail. If you have different levels of fitness, the stronger members can simply carry more weight. You can even hike with a group of friends as large as 12 people!
The GR10 can safely be hiked alone, and many people do so every year. Odds are that if you hike the GR10 alone, you will meet other like-minded individuals along the way, maybe by walking some sections together, or by meeting them in the hostels and on the campgrounds. Many people on the trail are French speaking, but most people who I have seen hiking the GR10 were not French and spoke English well. If you feel uncomfortable hiking alone, you could join a guided walk on the trail (see section on hiking with a group), or you could ask on the GR10 subreddit if anyone would like to join you for a section of your journey.
Planning and going on vacation with your spouse or family can be stressful. Even a beach vacation can be challenging for relationships that are not already stable. Hiking the GR10, and all the fatigue that comes with it, is not a good idea for every couple, especially if not everyone is fully on board with the idea.
That said, doing something you love can be a wonderful, shared experience. Besides some physical activity, the GR10 has many things to offer such as pretty scenery, interesting nature and geology, and culture of the towns you pass through.
Passing on the hiking experience to children can also fulfill a valuable part of their upbringing, by exposing them to mild hardships, their own achievements throughout the journey, and having them experience nature.
With a group of more than three, it is much more difficult to find accommodation at hostels and hotels. If you go camping, this should not be a problem, even on camping grounds with facilities or a hostel's camp ground.
A group offers little benefit in terms of safety as compared to hiking as a duo, except perhaps against dogs that live on some lands that you may cross. Luckily, this rarely happens and is usually not a problem when hiking alone or as a duo, but I imagine it is easier to face as a group.
The psychological dynamics of hiking the GR10 are probably easier with a group as you are less likely to get bored of one another. It is also possible to organically split up and regroup along the way. This means that the more physically fit people may choose to walk an extra detour to take in even more precious nature.
Not really. Many sections of the GR10 -especially the pretty ones- are national parks where dogs are not allowed to enter. This is because (some) dogs disturb nature by chasing the wildlife like marmottes and bears. In addition, you will be crossing other peoples' lands and they may have (agressive) dogs themselves. Bringing your own dog can cause issue with the dogs that are already present on private lands.
Almost all hotels, hostels, and commercial campsites do not allow dogs.