Keld Helsgaun
Keld Helsgaun is Associate Professor Emeritus in computer science at Roskilde University, Denmark. He received his MSc degree in computer science from DIKU at the University of Copenhagen in 1973. He has been at Roskilde University since 1975. His research interests include artificial intelligence (problem solving and heuristics) and combinatorial optimization. Contact Information:


Phone: (+45) 46 74 32 64

Mailing Address:
Computer Science, 10.1,
Roskilde University, P.O. Box 260,
DK-4000, Roskilde, Denmark


LKH - an effective implementation of the Lin-Kernighan traveling salesman problem heuristic.

LKH-3 - an extension of LKH-2 for constrained traveling salesman and vehicle routing problems.

ALMRRC - Winning the 2021 Amazon Last Mile Routing Research Challenge.

GLKH - a LKH-based solver for the equality generalized traveling salesman problem (E-GTSP).

CLKH - a LKH-based solver for the clustered traveling salesman problem (CTSP).

CGLKH - a LKH-based solver for the clustered generalized traveling salesman problem (CGTSP).

BLKH - a LKH-based solver for the bottleneck traveling salesman problem (BTSP).

jDisco - a Java package for combined discrete and continuous simulation.

javaSimulation - a Java package for process-based discrete event simulation.

COROUTINE - a portable C++ library for coroutine sequencing.

CBack - a simple tool for backtrack programming in C.

DISCO - a SIMULA-based language for combined continuous and discrete simulation.


Here are some of my publications.



Essential Computing II, Fall 2015

Computers and Networks, Fall 2014

Creating Software Systems, Spring 2014

Shared Memory Parallel Computing, Spring 2010

Object-Oriented Programming, Fall 2009

Algorithm Design with Internet Applications, Spring 2008

Project proposals: here.

Last updated: August 2021