Hybrid or Entry Level MTB if you're thinking of dirt trail riding. If they're some serious trails, switch that "entrylevel" to something more in keeping with the trails. If everything is paved - a hybrid should work just great for you and not be tooo heavy after your road bike!
Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, champagne in one hand, strawberries in the other, body thoroughly used up, totally worn out and screaming: "Yeah Baby! What a Ride!"