There is a huge percentage of the population that own a dog and many of them could not bear to go on holiday with out it. If you are going abroad, this can be extremely difficult and expensive as the dog will have to be in quarantine for a number of months prior to travelling and this alone can be distressful on the animal let alone the actual travelling.
If you are holidaying in the UK and are driving to your destination then you will need to ensure you have regular breaks where you can get the dog out of the car for a short while and have a drink before returning to the road. There are some dog friendly camping sites and even hotels dotted throughout the UK. You may still have to pay an additional fee to have a dog so always make sure that you specify this when booking.
You need to consider what you will do with the dog whilst you are out. It may be that you want to go out for an evening meal where you cannot take the pet and in this case need to be sure that the dog will not start chewing the furniture or spend the whole time barking while you are away.