We went up mount srdj early evening about 6pm August 2013 when it was not so hot. The view of Dubrovnik and Lapad is lovely, so dont forget your camera. There are two restaurant at the top, but a bit on the pricey side. The war museum is worth a visit, it will give you a bit more insight into the 1990's war. Allowed approx 1.5 hour for the war museum. I would recommend a trip on the cable car.