The modern world is characterized by motorization development that was not observed before. Motor traffic volume on the main traffic routes in large urban agglomerations often exceeds tens of thousands of vehicles per hour. Crossing a street in such circumstances has become very dangerous. In the same time railway network is also developed, including new high speed lines. Construction of numerous footbridges and underpasses that increase pedestrian safety and facilitate motor and railway traffic is necessary to separate pedestrian and vehicle traffic.
The modern man could afford to spend his free time in very attractive touristic regions. Need of visiting new touristic resorts, sight-seeing of richness of world's monuments, searching of calm places to take a rest, has led to rapid develop- ment of tourism. Thousands of people have nowadays access to places which, until recently, were visited by few. For instance, the footbridge in Sromowce Niżne (a highly attractive tourist destination), in the mountainous Polish-Slovak border region, is used by over 15 000 people every weekend.
Fragment Wstępu