Can be a photo from a show or whatever, you don't have to know the horse, just have to own the picture/horse. No pics pulled off of google
Here are the thickest necks I have seen:
This is Pepper. He is Rumour's grandsire. A 10 yr old Clydesdale(with possibly Friesian in him). He's a gelding now.
Sterling. Pepper's son. A Clydesdale X Belgain. He is 6 yrs old.