I recently rebuilt this 312-3 Cargo Ship from 1973. At the same time I rebuilt a whole stack of other sets from the same era. Even the most sentimental Lego fan would have to admit that most Lego sets have got a lot better since 1973. We now have minifigs, and the cars and aeroplanes are so much better now. However, these 1973 boats remain the best Lego have ever produced.

The hull is made from eight stud long sections that click together; a bow, a stern and three central sections. Each section is hollow and watertight, and so each section provides buoyancy which is immune from flooding. The set came with a weighted keel with studs that can be clicked on to a row of anti-studs on the bottom of each hull section. When the keel is attached the whole boat is surprising sea worthy. Even though I can't find it on the Brickset data base, you could even buy a battery powered motor with a propeller and a rudder that you could click onto the bottom of the boat behind the keel to allow the boat to run through the water. The bow section also has a loop that string can be attached to so that the boat can be pulled through water.

The ship's superstructure is built on top of the studs on the deck surface of these hull sections. The superstructure is not overly elaborate by modern standards, but looks quite cool in its depiction of a pre-containerised cargo ship. This set probably had the most elaborate of all the 1973 boats and was the longest. The hull sections can be rebuilt to make a ship of any length, only restricted by the number of hull sections you have. You can then build any superstructure you like on top of your hull.

The sets came with stickers, that represented portholes, anchors and some 'Legoland' branding. From memory the stickers where like the decals that you would apply to model aeroplanes. You soaked them in water and then slid them off the cardboard on to the model before allowing them to dry. The interesting thing about these stickers is that, despite spending a lot of time in the water in the 1970s, these stickers still look brand new today.

This boat allowed children to build boats of four different lengths (0, 1, 2, or 3 central sections), and build whatever superstructure they wanted to on top. Any boat you make with this set will float, not risk becoming flooded, and stay upright (thanks to the keel). The stickers can be immersed in water without damage. What Lego boat since then has offered both the flexibility of future builds and the play value in water that this set offered?

A great set. These 1970s boats were brilliantly designed toys for children.