Using fill flash was probably not the only way to go in that situation because it probably eliminated the "mood" of the shot by opening the shadows and showing unnecessary detail. Question the reason why you captured the image and what drew you to it in the first place.

A neutral density filter would have uniformly darkened the overall image by letting in less light. Neutral density filters are usually needed in two kinds of situations. If you can't control the brightness of the lighting and it's too bright for the camera settings you want to use, like if you want to use limited depth of field but can't get a fast enough shutter speed. The other use is to show motion by allowing camera settings that blur the subject. Like capturing flowing water in a waterfall.

I should add that there are graduated neutral density filters that allow detail to be captured in a light sky while properly exposing the foreground.

Thanks Larry,
I really think in the case of the shot I took might had been a benifit because of the harsh light coming through the sides. A longer exsposure might have helped if I could have kept from over exsposing the image which might have given more what I wanted. I will post the image so you can see. Monte Johnson.

Here is the image. So you might get a better idea. I brought it out a little in Photoshop.

A longer exposure wouldn't make a difference if the meter reading was accurate. What you need is less light in the bright areas. In Photoshop you can combine two exposures for a wider dynamic range. Shoot one for the shadows and one for the highlights. But you will need to use a sturdy tripod. There is also an inexpensive plugin from Fred Miranda that does the same thing.

Thanks Larry. I welcome the insight. Monte Johnson.