Mathematics named after places Chinese Remainder Theorem is perhaps the most famous piece of mathematics named after a country. Another example, although less famous, is the concept of a Polish space. What other theorems, concepts or objects are named after a geographic region, a city or any other type of location? 
 A: In mathematical finance, there is a convention of naming various styles of options after places.  American and European options are the most common, but I've also heard of:


*

*Asian options

*Russian options

*Bermuda, Canary, Verde options (partway between American and European)

*Boston options

*Parisian options
A: Berkeley cardinals are a type of large cardinal.
(And I guess one could argue about whether worldly cardinals count.)
A: Steiner's Roman surface is a continuous image of the real projective plane into $\mathbb{R}^{3}.$ It has its name because the parametrization was discovered by Jakob Steiner while he was in Rome in 1844.
A: The famous Königsberg Bridge Problem certainly qualifies, and was the first that came to mind for me.
A: The SNCF metric has the property that to pass from point A to point B you have to pass via Paris.
A: The Method of Four Russians is a technique for speeding up algorithms involving Boolean matrices, or more generally algorithms involving matrices in which each cell may take on only a bounded number of possible values.
It is unclear whether all the four authors were in fact Russian at the moment of publishing the paper. It is known that at least two of the four authors (Arlazarov and Kronrod) were actually born in Moscow. While Kronrod died in Moscow in $1986$, Arlazarov still lives and works in Moscow as of $2016$.
A: Polish and reverse Polish notation.
(Not to be confused with Hungarian notation, which this is definitely the wrong SE site for.)
A: There exists a list on Wikipedia about this: 
https://en.wikipedia.org/wiki/List_of_mathematical_concepts_named_after_places
A: What about mathematics created by mathematicians whose surnames were derived from names of cities? Would that count? If so, here are some examples:


*

*The Győri-Lovász theorem was named after Ervin Győri — Győr, Hungary.

*Presburger arithmetic was named after Mojżesz Presburger — Pressburg (Bratislava), Slovakia.

*Razborov-Smolensky polynomials were named after Roman Smolensky — Smolensk, Russia.

*Szegedy quantum walks were named after Mario Szegedy — Szeged, Hungary.

*Wiener processes were named after Norbert Wiener — Wien (Vienna), Austria.
A: The Wonderful Demlo numbers were named by D. R. Kaprekar for an Indian train station.
(Where is that town/station? What are its geographical coordinates, and does it still exist today?)
A: The Monte Carlo method, Monte Carlo algorithm, Las Vegas algorithm, and Atlantic City algorithm have an element of randomness in common.
A: Does Manhattan norm (here) count as such?
A: Tropical geometry was named in honor of the (Hungarian-)Brazilian mathematician Imre Simon.
A: The word  algorithm is derived, through medieval Latin from Khiva (Uzbekistan). The 9th-century mathematician Abū Ja‘far Muhammad ibn Mūsa, author of   works on algebra and arithmetic, was called al-Ḵwārizmī ‘the man of Ḵwārizm’. In fact, algebra is a term form medicine used in one of his books Hisab al-jabr w'al-muqabala.
His name entered the language (influenced by Greek arithmos ‘number’) through Old French from medieval Latin algorismus. He is depicted below.

As far as I known, the concept of algorithm derived from his (first?) complete solution to the second degree equation, divided in six different cases, taking into account that dealing with negative numbers and the zero was not natural at that time.
Aside, the polar co-ordinate  system seems the most obvious. And yes, we have two poles. The exact origin is not clear to me. However, the Polar coordinate system, used in astronomy in ancient times, was slowly extended into a genuine coordinate system, related to the poles

The calculation is essentially the conversion of the equatorial polar
  coordinates of Mecca (i.e. its longitude and latitude) to its polar
  coordinates (i.e. its qibla and distance) relative to a system whose
  reference meridian is the great circle through the given location and
  the Earth's poles, and whose polar axis is the line through the
  location and its antipodal point.

