I Need ideas on how to keep food warm for a party at a park?

Try sterno, they are small burners you put under chaffing dishes. Light by match, caters use them.

Thermol Coolers

Can Keep food Warm or Cold as long as you don't put some cold in with the warm..

and there are some Hot & Cold bags that keep food how you want it..

use crock pots if you have access to electricity borrow the crocks from friends and bring extension cords. you can buy aluminum throw away pans with a stand like restaurant's use on buffet tables the food stays warm by the sterno cans lite underneath you can use several of those small tea light candles also. have a great picnic.

Yep everyone else is so right. Tried it and done it. You can also keep it covered and that helps in keeping things warm and not keeping flames lite on the sterno warmers and overcooking or burning your food.

You can place the cooked/warm food in a cooler. It wil keep it warm. Just don't add ice, lol.

Depends on what part of the country you are in. Here in the Southwest you could just set it out on the table and it would cook in an hour or 2. Then you would have to have some shade for it.

Use thermal bags . they are specially made to keep food warm.

Little cans of sterno under a rack set-up might do it.

Keep it in the microwave with the door shut for xmas parties etc.

Coolers don't just keep cold things cold; they generally keep warm things warm too. This is why pre-cooking hot meals is a BAD idea at parks and picnics. Sandwiches are a better bet, or grilling there. If you precook, then why bother going to the park?

I don't think you planned this out very well.