Wayne manor? It certainly could be. Although it doesn't really look big enough to be honest. But who else would have the bat symbol in their pool? Just some rich a-hole with more money than he (I suspect it's not a girl, otherwise it would be a stiletto) knows what to do with? I guess you're right. That would certainly explain the tennis court. But riddle me this (just like the Riddler!) then: why did I see Batman and Robin skinny-dipping in the pool late last night? Because they like watching each other's wieners flop around all crazy-like when they go off the diving board? Yeah, that actually was pretty funny. Then they made out in the woods. I watched the whole thing with night-vision goggles. Green weenies.
One more zoomier picture after the jump.
Thanks to dealmaker7883, Casey, Jed, Sgt Rebel, Miss Bowser and gpspud20, who are all convinced the entrance to the Batcave lies underneath the tennis court. Pfft, amateurs. There's obviously an elevator under the table umbrella.