Humidity
After seeing some sites that were not doable that hot, humid day, our group of three became restless... a giant power plant that doesn't look too used sounds like a great idea!
The new facility looked pretty neat, but upon entering a flooded room, my hair stood on end from the electricity in the air - you could taste it. All this water and power was probably not a good idea safety wise, and not knowing who could be working or patrolling there could be a real problem (especially post 9-11). So the older coal plant it was - and it was great! The machinery had been stripped out but the gorgeous architecture remained. It was well worth the sweat!