“We can infer that he and Antinous went there, and memorably enjoyed themselves. Hadrian would not have been Hadrian without finding time for a hump.”
Wait, what? Oh, you said “time for a hunt.” Never mind.
Works either way. 
By the way, I get this one without googling due to the exhibit at the Art Institute of Chicago. If nothing else, Antinous shows there was a way to get a town named after you other than military conquest.