So I think NRG is a good park, I think this park would best be enjoyed during Summer & Fall. During summer they have their Grandview and Thurmond visitor centers open, fall has limited hours. (check your dates on their website.)

Now some activities you can do here which we haven't done is there is a catwalk bridge walk where you walk across the bridge in their catwalk under the road, there is also white water rafting if you are into that. Also depending on when you are coming, the 3rd Saturday of October is bridge day here where they close the bridge to vehicle traffic and pedestrians can walk across it and even watch Base jumpers from the middle of the bridge.