In the section where te mill is there are 2 clusters of hay get in between the two and push them apart then you will see the hatch that was beneath them then use the key to open it
you just click it.
The small key in Astro Knights Island is for Mordred's secret hideout. When you come to that wind mill area, move the hay bales apart and use the key on that.
the door that's locked
On a giant asteroid in the asteroid belt.
just click it.
The secret room between the hay bales!
it's in the astro belt at the bottom left coner area.you have to defeat the planets and have all the knights with you to get to the castle. once you have all the knights with you go to the astro belt then, go to the sword key and pull it out. after that you jump in the spining wheel thing.
you get the green stuff an dthen put it in
The key on the big asteroid in Astro Knights Poptropica is located in the lower right corner of the asteroid near the entrance to the base. You need to use the bridge to reach it, but be careful of the falling debris.
put the manure that i dude gives you in it.
get the fuel and put it in the rocket ship and put in 56 and 52.
The key unlocks mordreds secret lab. You can get there by seperating the two hay bales.