Hi Sam

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I hope you have a great time!, The Grand Californian is lovely, the rooms are wonderful (some even overlook Grizzly Peak) and it is so convenient to all of the parks and DTD. The hotel has two pools and a health club which is also very nice, plus a wonderfull grand lobby which is like a mixture of The GF and WL. Since the hotel is near a main road, you may get a room facing the road (which can be noisy) it might me worth asking them for a specific view (they are very friendly and when we visited we asked if it was possible to change rooms and they done it immediately

)
Don't Miss -
Disneyland Park-
Indiana Jones Adventure (one of my favourite Disney rides, ever!) You board 4x4 jeeps and race through lots of Indiana Jones Adventures.
Pirates of the Caribbean - A much better version.
Matterhorn Bobsleds - A great rollercoaster, although a little rough.
Fantasmic - IMO, the Californian version is MUCH better than the MGM one! (There is sometimes 2 performances a night, If you can, go to the second one were it is easier to get a place on the grass (there are no benches) )
California Adventure -
There are lots of don't miss rides here but the absolute best has to be -
Soaring over California - This is simply a perfect ride, as I am sure you will find out. It is a hang-glide simulator that offers a wonderful experience of site, feel and smell - you have to ride it to believe it. This ride is just breathtaking (one lady next to us even started crying at the end, she said it was the best experience of her life)
Also Be sure to stay for the Disney Electric Parade, which is scheduled for just before closing.
As for eateries in Disneyland Park we really enjoyed meals at:
Blue Bayou Restaurant (backing pirates of the caribbean!) and we loved having a snack at River Belle Terrace (in Fronteir Land of DL Park) - they have wonderful Mickey Mouse Pancakes! Also, there is wonderful barbecued meats at The Bengal Barbecue.
I seemed to have gone on a bit too much, but its not often I talk about DCA!
Have a great time! If you have any more questions I will hopefully be able to help
