About 4km southeast of town are the 30-plus underground Cantalloc Aqueducts, many of which are still in working order and are essential in irrigating the surrounding fields. The impressive series of stone and wood channels and spiraling access ways were built by the Nazca between AD 200 and 900 and are considered one of the finest examples of pre-Hispanic engineering. Locals say the water here is still good to drink.
Though once possible to enter the aqueducts through the ventanas (windows), which local people use to clean the aqueducts each year, it's no longer permitted to go all the way in; instead, you can take note of the Nazca’s exceptional stonework from the outside.
It’s possible, but not necessarily safe, to walk to the aqueducts; at least, don’t carry any valuables. Alternatively you can hire a taxi to take you there for S4 to S5. To get a return taxi you will probably have to walk out a few minutes to the Cooperativa Cantayo.
Admission is via the Boleto Turistica which also covers entry to the nearby Paredones ruins and El Telar, a geoglyph found in the town of Buena Fe. Tours from Nazca take 2½ hours, cost from S30 per person and may be combined with visits to touristy gold and ceramics workshops.