Is it normal for a toddler to nap for HOURS

My almost 2 year old takes very long naps. He is tired at 1:00 pm and naps until 5 or 6 sometimes.

Pushing his bedtime to 10pm.

I’ve tried moving his naps earlier but he still sleeps for very long hours. I put him down at 11am and he will wake up at 3pm. I’m always checking on him and he’s always zonked out completely. Is this normal? He gets plenty of nighttime sleep. He will nap anywhere from 3-6 hours. I thought he was laying awake for a while and then falling asleep after an hour or so but he doesn’t do that every time. He just will always nap for a long time. I didn’t think it was an issue until now because yay for long naps right, but how long is to long?