ABSTRACT A multimodal trip planner that produces optimal journeys involving both public transport
and private vehicle legs has to solve a number of shortest path problems, both on the road
network and the public transport network. The algorithms that are used to solve these shortest
path problems have been researched since the late 1950s. However, in order to provide accurate
journey plans that can be trusted by the user, the variability of travel times caused by traffic congestion
must be taken into consideration. This requires the use of more sophisticated time-dependent
shortest path algorithms, which have only been researched in depth over the last two decades,
from the mid-1990s. This paper will review and compare nine algorithms that have been proposed
in the literature, discussing the advantages and disadvantages of each algorithm on the basis of
five important criteria that must be considered when choosing one or more of them to implement
in a multimodal trip planner.