I think the cost is a little high (RM70 for 2 adults 2 kids) for the amount of things you can do up there; but I have also seen more ridiculous costs elsewhere. We went on a weekday, so the crowd is smaller. The train is airconditioned. I think wheelchair access is for one cabin of the train only, and the staff have to help. The train speed is about 10m/sec at its fastest, if I remember correctly. The temperature is a little cooler, but no sweater needed. I'm the kind of "fast" visitor so my thoughts could be a little skewed in that sense. The view is what you'd expect from on top of a hill at about 500m above sea level. The pictures will give you a far better idea.
There's a trail for a nature walk but I didn't go on it. There's an Indian temple and a small mosque next to it and a small playground in between them. There are a few guys who offer to take visitors for a ride on their golf buggies for RM30 around the area at the hilltop.
I like the view best. If you go, wear comfy walking shoes, a hat and sunglasses. I'd say the place takes only about 2 hours top. You can take taxi there and there are many taxis at the bottom waiting to take visitors away too. Alternatively, you can walk to the main road and get on a bus to Komtar, which has a bus interchange. Taxi ride will probably cost about RM30something. The bus ticket is RM1.40. The buses are clean and wifi ready (but I didn't get a chance to try the wifi). The frequency of the buses is a bit disappointing though, so the locals say. So if you get there and one just left, it may be a 20-30min wait.
One last thing--may be a good idea to call and find out if the Hill train is working before you go. They shut it down sometimes for repair. This is the phone no. from their visitor website: 04-8288880/39
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