Addresses in Puerto Rico (especially in and around San Juan) can be confusing, because Spanish terms like avenida and calle are used interchangeably with English terms like avenue and street. This means that the shopping strip in Old San Juan may be called Calle Cristo or Cristo Street (and it might just be called "Cristo," as it is on many maps). A highway is often called an expreso, and an alley or pedestrian-only street is labeled a paseo.
Outside a metropolitan area, addresses are most often given by the kilometer mark along the road. That means that the address for Parque de las Cavernas del Río Camuy, south of Arecibo, is given as Route 129, Kilometer 18.9.