finding a building by its address a challenging task. In some cities, especially hosting large scientific or military research centers in Soviet time, the numbering might be different: houses may have numbers related to the block rather than the street, thus 12-й квартал, дом 3 (Block 12, House 3), similar to the Japanese and Korean systems. Aktau is one example of this. When a numbered plot contains multiple buildings, they are assigned an additional component of the street address, called корпус (building), which is usually a sequentially assigned number unique within the plot (but sometimes contains letters as in 15а, 15б, 15в and so on). So, a Russian street address may look like Московское шоссе, дом 23, корпус 2 (Moscow Street, plot 23, building 2), or Льва Толстого, дом 14б (Leo Tolstoy Street, plot 14, building b). On very long roads in suburban areas, a kilometer numbering system also may be used (like Australian rural numbering system). For example, 9-й км Воткинского шоссе (9th kilometer of Votkinsk Highway), and Шабердинский тракт, 7-й км (7th kilometer of Shaberdy Road). Latin America In Latin America, some countries, like Mexico and Uruguay, use systems similar to those in Europe. Houses are numbered in ascending order from downtown to the border of the city. In Mexico, the cities are usually divided in Colonias, which are small or medium areas. The colonia is commonly included in the address before the postal code. Sometimes when houses merge in a street or new constructions are built after the numbering was made, the address can become ambiguous. When a number is re-used, a letter is added for the newer address. For example, if there are two 35s, one remains as "35", and the second one becomes "35A" or "35Bis". It is sometimes common in remote towns or non-planned areas inside the cities, that the streets do not have any name and the houses do not have numbers. In these cases, the address of the houses are usually the name of a person or family, the name of the area or town, or Dirección Conocida ("known address"), which means that the house of the family is known by almost all the community. This kind of addressing is only used in remote towns or small communities near highways. For people living near highways or roads, the usual address is the kilometer distance of the road in which the house is