If you want to go trekking in the Cordillera Blanca and the Huascarán National Park then go to Huaraz, in the Ancash region. Once there you can choose your itinerary. Be careful, prices that are too low are often suspect. Safety should be your first concern, so go on the trek with a guide and mule drivers.
Huaraz is a trekkers paradise, at the foot of Huascarán, Peru's highest mountain (6,768 m) in the Cordillera Blanca. It is this mountain that has given its name to the amazing Huascarán National Park, which is a UNESCO World Heritage site. And you can see why: the whole time we were trekking in the Cordillera Blanca we were surrounded by glacial lakes, waterfalls, mountain streams and other snowy passes and peaks.
To get to the village of Hualcayan we took the bus from Huaraz as far as Caraz. Then we walked! This trek is ideal for getting acclimatized to high altitudes before trying your "first 6,000".