How to build a 300-foot hill suitable for skiing

[Erazman]

What would be the easiest way to build a 300 foot hill -- one with a slope gentle enough to ski on in the winter?

 

[Danger]

Do you mean 300 ft long, or 300 ft high? Either way, you've got your work cut out for you. I'd really try to find a pre-existing one, but I suppose that you've already ruled that out. You'll need heavy equipment, in any event. Maybe if you sweet-talk Brewnog enough, he'll send over one of those nice big yellow toys.
My strictly amateur opinion is that you should cut your work in half by excavating a long, sloping trench to half of the height (depth) that you want, and piling the dirt up in a matching ramp that extends from it. That way you'll have a 300 ft high slope, but only 150 ft needs to be built up.
Very seriously here, despite that it might sound like a joke: I'd approach everyone in your vicinity and see if they'd be willing (if zoning allows) to start a landfill type setup on your property. Once there's enough garbage (meticulously compacted, of course) piled up, you can cover it with a layer of dirt and be done with it. You'd have to check into all of the possible negatives, though, such as smell, spontaneous combustion, etc..

 

[civil_dude]

I agree, but you will wind up with a large hole which will need pumps and have to ensure that your cut slopes are stable.