In the eternity that HL2 was developed, several videos were released and other tidbits of content were leaked.
In these small vids and bits of content, several scenes were depicted. One of which is set in a sewer type area with Alyx Vance. A Combine dude drops in and a blueish 'hydra' creature skewers him and shakes him around. Not in the released game. Another one involves the coast. The background is not mid-day as currently in the game, but a sunset. Several zombies are also present. Much more probably exists, but I can't think of anything right now.
I'll try and dig up some links to these vids (they're massive IIRC)... It's a shame they were removed from the final product. Anyone know why? I don't think a 'time constraint' is a viable excuse.. Valve had all the time in the world and then some
