Mathematical ideas named after places This question is quite unimportant, so feel free to close if you think it is inappropriate.
I've been thinking about how mathematicians come up with names for the ideas/objects they study, and how that differs from the practices of people in other fields.
It seems that almost always we do one of two things: 1) we pick a name that describes some feature of the object (sometimes not very well, e.g. flat modules, sets of second category), or 2) we name it after a person (who may or may not have studied that object).
Very rarely we name something after a place. (This is much more common in other fields.)
I can think of only 3 examples:
*Japanese rings
*Polish spaces
*Tropical geometry
Does anyone know of any other examples in mathematics?
 A: The Chinese remainder theorem.
The Mexican hat wavelet.
Arabic (or Roman) numerals.
A: The Erlangen program.
A: "The Roman surface (so called because Jakob Steiner was in Rome when he thought of it) is a self-intersecting mapping of the real projective plane into three-dimensional space, with an unusually high degree of symmetry."
http://en.wikipedia.org/wiki/Roman_surface
A: Italian squares which include Latin squares, Tuscan squares, Roman squares, Florentine squares and Vatican squares as special cases.
A: Nottingham group
A: (Non-Serious)
Well, depending on how far you wish to stretch the term "place"
Midpoint Method
A: The Scottish Book, named as you know for the Scottish Cafe in Lwow where Banach and his friends would meet and discuss mathematics.
A: Aarhus integral, Polish notation, English/French notation (or something like that - it refers to different ways to draw Ferrers diagrams - or was it English/Italian?), Tower of Hanoi, Russian constructivism (Russian school of intuitionism).
A: Las Vegas algorithms. 
A: There is Colmez's "Montréal functor" which is part of the $p$-adic local Langlands business. The story is he introduced it in a lecture in Montréal.
A: The Woods Hole formula, as that is where there was a race to prove this Riemann-Roch-Lefschetz formula.
A: Two more are:
Egyptian fractions
Canadian Traveler Problem
A: Nowhere differentiable: named for Ainsworth, Nebraska, I believe.
A: Perhaps a stretch, but in mathematical finance it is traditional to name option styles after places.  American and European are the most common, but http://en.wikipedia.org/wiki/Option_style also lists Bermudan, Canary, Asian, Russian, Israeli, and Parisian.
A: There's a Four Russians algorithm in computer science.  I don't remember what the algorithm did or who the four Russians were, but the description "named after the cardinality and nationality of its inventors" stuck in my mind.  I think that description is from the first edition of Principles of Compiler Design (aka the Green Dragon Book) by Aho and Ullman.  (Googling finds some descriptions of the algorithm).
A: The Delian problem.
A: universal example?
A: Loops (aka quasigroups with identity):

It was at this point that the terminology of quasigroup theory underwent a
  historic change. It became apparent that it was necessary to distinguish between
  two classes of quasigroups: those with and those without an identity element.
  A new name was needed to designate the system with identity. This occurred
  around 1942, among people of Albert’s circle in Chicago, who coined the word
  “loop” after the Chicago Loop. For Chicago locals, the term “Loop” designated
  the main business area and the elevated train that literally made a loop around
  this part of the city.

(taken from Historical notes on loop theory, by Hala Orlik Pflugfelder)
A: Dubrovnik polynomial
A: The Cracovian algebra- of matrices with some non-associative multiplication
http://en.wikipedia.org/wiki/Cracovian
A: The French Railroad metric: if $(X,d)$ is a metric space, and $p \in X$, define $d_R(x,y) = 0$ if $x = y$ and $d_R(x,y) = d(x,p) + d(y,p)$ otherwise. Apparently named so because almost every train in France goes trough Paris.
A: The Conway-Paterson-Moscow theorem
A: While visiting the city in question, Nesetril defined an ultrafilter he called a Riga P-point.
A: Two amusing examples from distributed computing are:
The Bysentian generals problem.  The problem asks for an algorithm that allows a large number of processors to reach a consensus on something (say a bit value) when some of the processors behave in a malicious way. The original paper motivated the problem with a fictional account of Byzantine generals trying to coordinate a joint attack. There's also a related "Chinese Generals Problem".
Paxos algorithms. This is a family of algorithms that also allow a number of participants to reach a consensus. These were introduced by Leslie Lamport in paper written as a story about the downfall of an ancient Parliament on the (fictional) island of Paxos. The story ends when the parliament inadvertently restricts membership to dead sailors which, of course, can then not be corrected. As you can read about here, the novel exposition of the paper led to a very delayed publication of what has since been recognized as an important result (and is reportedly used in Google, Microsoft and IBM products).
A: The Warsaw circle is a motivating example in shape theory.
A: Königsberg bridge problem
A: The Hawaiian earring:
http://en.wikipedia.org/wiki/Hawaiian_earring
The space H is homeomorphic to the one-point compactification of the union of a countably infinite family of open intervals. 
A: Topos (sorry!)
A: Toronto space.
A: Japanese theorem for cyclic polygons
Monte Carlo method
Hungarian Algorithm
A: anarboricity of graphs (named in honor of the city of Ann Arbor by Frank Harary, but also having something to do with non-trees (http://mathworld.wolfram.com/Anarboricity.html)
A: Manhattan distance
Chinese restaurant process
A: The Aarhus integral of rational homology 3-spheres
http://arxiv.org/abs/q-alg/9706004
A: Swiss cheese (one type in complex analysis, another in cosmology)
A: The Oberwolfach Problem and the Hamilton-Waterloo Problem
A: Look at http://blogs.ethz.ch/kowalski/2010/08/19/what-countries-are-mathematical-objects/
A: K. Barré-Sirieix, G. Diaz, F. Gramain and G. Philibert proved the Mahler–Manin conjecture in St-Étienne, so the result is now called the "Theorem of St-Étienne" (see Hida's book Hilbert modular forms and Iwasawa theory, p. 62). The theorem states that the Tate parameter of an elliptic curve $E_{/\overline{\mathbf{Q}}}$ with split, multiplicative reduction is transcendental (over $\mathbf{Q}$).
A: The semi-symmetric Ljubljana graph, from algebraic graph theory. 
A: Black Cow Factor in Optimal Cloning of Pure States by R.F. Werner (arXiv:quant-ph/9804001). He writes,

"The reason for this terminology is that it plays an important role in discussions of the
cloning problem started by Chiara Machiavello and Artur Ekert at the Black Cow Café in
Croton-on-Hudson, NY, and further clarified in collaboration with Dagmar Bruß [BEM].
I learned about this line of argument from a set of “Black Cow Notes” by Nicolas Gisin
and Sandu Popescu."

A: The Arctic Circle Theorem (http://arxiv.org/abs/math/9801068)
A: outer space
A: In computer science, the Vienna Definition Language, or the related Vienna Development Method.  (A tool for definining program semantics).
A: What if named after a person who derives his name from a place?
e.g. Hamburger expansion
How about moonshine? If moon is allowed, why not Stone (as in Stone-Weierstrass)? And then Stein manifold, Einstein metric, Eisenstein criterion? 
There are also buildings and chambers and apartments of Jacques Tits.
(BTW, is the last word of previous sentence a place?)
A: Italian Algebraic Algebraic Geometry
One that is not but I used to think so: Catalan number :)
