Question: What is the name of the valley that the city 50 km northeast of The Estancia Maradona is located in?
Sentence (from "San Juan, Argentina"): San Juan (] ) is the capital city of the Argentine province of San Juan in the Cuyo region, located in the Tulúm Valley, west of the San Juan River, at 650 m above mean sea level, with a population of around 112,000 as per the 2001 census (over 500,000 in the metropolitan area).
Relevant evidence: Yes