I do not know much about this district east of San Isidro, but while walking around I did notice an unusual number of Asian owned businesses including restaurants. This area seemed to be a small Chinatown of sorts, but that's only based on my personal observation. I also noticed quite a few Asians using the saunas in this area.
King Spa - Ave. Aviación 2938: King Spa in San Borja is one of two in Lima, the other in Lince. Unlimited use of wet and dry saunas and jacuzzi is only 20 soles ($6 USD). Massage is 20 soles more, but you'll have to negotiate for additional services beyond that. The King Spas are great places to use their saunas for refreshment, but there are many better P4P options.
Gold Spa - Ave. Aviación 3360: Gold Spa was nicer than the King Spas in both categories of facilities and in the lineup of ladies based on a couple visits to all three. Various toiletries are provided here, allowing one to really clean and freshen up after a long day, or to jumpstart an evening. Like the other saunas there are not a lot of ladies available, but the ones I saw were a tad more attractive than the Kings. I chose one here that looked in better shape while in clothes and had a mediocre experience on the small massage table, but I still like the facilities.
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