The aim of this paper is to present an analysis of the main factors influencing negatively Klaipeda Sea Port performance and competitiveness as well as their limiting impact on the development of this transport system entity in general. This case study research is proposing some alternative solutions decreasing negative influences of comparatively declining land transport infrastructure connectivity to the Sea Port hinterland. Analysis of hinterland connectivity is based on the extended gate concept, where a series of terminals and related logistical activities are integrated into a functional single entity. The intensity of real road transport flows on the main connecting road intersections has been evaluated using digital tools with input data from the ArcGIS platform. Also, accessibility to other terminals (at the local, regional and global scale) as well as the terminal is linkage to the regional transport system has been taken into account. One of the objectives of this research was to define objectively the state of traffic flow on the highway connecting Klaipeda sea-port to its hinterland because the road infrastructure was not qualitatively improved for a long period, while the average annual seaport turnover is constantly growing by 6% -9%. Secondly, it was defined how substantially is possible to decrease the load of road traffic in case of reestablishing of an inland waterway connection between practically the same points of the transport route. Using mathematical modeling of traffic flows is proved that, road transport highway connection in/from the Klaipeda Seaport is loaded substantially and requires systemic improvement (building at least additional lanes in both directions, etc.) to promote further growth of Klaipeda sea-port capacities. The option to apply an additional inland waterway connection allows to decrease the road traffic flow up to 9 -11% with the possible development of this option, what in its' turn also decrease the negative influence on the environment.

In case of planning transportation of Oversized and Super heavy Cargo (OSSHC) we always meet two fundamental constrains – the time of completing the task and the financial costs of implementation. Also, the decision-making process should be as much as rational, uncomplicated, efficient and inexpensive. The importance of fundamental constrains mentioned above could vary because of specific circumstances impacting the decision maker. The essence of the Unified Criteria System (UCS) is to create a possibility to recalculate time and financial cost values into the Unified Criteria Unit. In case of correct access, the evaluation process is implemented comparing summed amounts of criteria points of each evaluated variant including means of transport, route, etc. The importance of findings is that UCS allows us to assess objectively huge number of variables (more than 50) concerning the process of transportation, including infrastructure improvement, legal, social obstacles, etc. without the time and money consuming extensive calculations and this empowers the decision maker to evaluate qualitatively and quickly choosing the most preferable alternative. The work deals with the possibilities of transportation of super heavy and oversized goods by road vehicles, railways, inland waterway vessels and trans-shipping of the cargo in Klaipėda State Seaport as well as application of the aforementioned modes of transport in multimodal transportation operations. Potential problems that may impede transportation or make the carriage practically impossible have been also assessed, variants of solutions of the problems are also provided.