Building model bridges with LEGO blocks is quite interesting. The LEGO set will include tracks that are curved, straight and flexible. You will also find switch tracks and crossovers in the set. These blocks offer a great deal of flexibility when it comes to designing your own set of bridges. You will find that there are no dedicated model bridges in the LEGO train set. But it is possible to assemble the blocks to form foundations of the bridge in several different ways. The easiest and most common way to do this is by forming triangular trusses using the blocks. These are fairly strong enough to support the weight of a LEGO train.