Runners in colorful dinosaur costumes turned out for a race up a grassy ski slope in Katsuyama City, Fukui Prefecture, on Sunday.
The event is intended to give a boost to the central Japan city, a known fossil hot spot.
More than 100 participants ranging in age from one to 74 first changed into T-Rex suits and did warm-up exercises.
The races were divided into four categories, including age groups. The contestants did their best to sprint uphill but some fell as spectators cheered them on.
One woman who took part said it was tough going, but she had fun.
The race for males of junior high school age and above went to a 31-year-old from the prefecture’s Sakai City.
He said this was both his first time in the costume and his first race, so he is happy with the win. He added that he wants to defend his title next year.