**Interesting/widely used implementations of pathfinding algorithms. 
==========================================================================

A*                                      Ruby    https://github.com/georgian-se/shortest-path
A* (bidirectional with shortcuts)       C++     https://github.com/valhalla/valhalla
A*                                      Unity   https://arongranberg.com/astar/front
NBA*                                    JS      https://github.com/anvaka/ngraph.path
NBA*                                    Java    https://github.com/coderodde/GraphSearchPal
NBA*                                    Java    https://github.com/coderodde/FunkyPathfinding
NBA* (Parallel)                         C++     https://github.com/janhsimon/PNBAStar
Multi-Level Dijkstra (CRP)              C++     https://github.com/michaelwegner/CRP
Multi-Level Dijkstra                    C++     https://github.com/Project-OSRM/osrm-backend
Multi-Level Dijkstra (SARA)             Java    https://github.com/cc-routing/routing-sara
Pruned Highway Labelling                C       https://github.com/kawatea/pruned-highway-labeling
Pruned Landmark Labelling               C++     https://github.com/iwiwi/pruned-landmark-labeling
ALT                                     Java    https://github.com/graphhopper/graphhopper
ALT                                     Java    https://github.com/jgrapht/jgrapht
ALT                                     Python  https://github.com/ryanpon/pathfinding-animator
Contraction Hierarchies                 Java    https://github.com/graphhopper/graphhopper
Contraction Hierarchies                 Java    https://github.com/michaeltandy/contraction-hierarchies
Contraction Hierarchies                 Java    https://github.com/navjindervirdee/Advanced-Shortest-Paths-Algorithms
Contraction Hierarchies                 JS      https://www.mjt.me.uk/posts/contraction-hierarchies/
Contraction Hierarchies                 C++     https://code.google.com/archive/p/monav/source/default/source
Contraction Hierarchies                 C++     https://github.com/Project-OSRM/osrm-backend
Contraction Hierarchies                 C++	    https://github.com/payasr/contraction-hierarchies
Contraction Hierarchies                 Java    https://github.com/cc-routing/routing
Contraction Hierarchies                 C#      https://github.com/itinero/routing
Contraction Hierarchies                 Rust    https://github.com/easbar/fast_paths
Customisable Contraction Hierarchies    C++     https://github.com/RoutingKit/RoutingKit
Edge Hierarchies                        C++     https://github.com/Hespian/EdgeHierarchies
Time-Dependent Contraction Hierarchies  C++     https://github.com/GVeitBatz/KaTCH
Highway Hierarchies                     Java    https://github.com/biafra23/mapsforge/tree/master/src/org/mapsforge/android/routing/blockedHighwayHierarchies
PHAST                                   C++     https://github.com/vlarmet/cppRouting
Hub Labelling                           C++     https://github.com/savrus/hl

*** Stochastic Routing ***
SOTA                                    Python  https://github.com/mehrdadn/SOTA-Py

*** Generalized Routing Frameworks ***
Multiple Algorithms                     C++	    https://github.com/vbuchhold/routing-framework
Multiple Algorithms - CH/CCH/...        Rust    https://github.com/kit-algo/rust_road_router

*** Other Types of Routing ***
k Shortest Paths with Limited Overlap   C++     https://github.com/tchond/kspwlo

*** Other lists of routing algorithm papers and implementations ***
Advanced Routing Algorithms                     https://github.com/bcgov/ols-router/issues/25