The way things change a whole awful lot over the years. The way cities and other landmarks appeared decades ago is not how they appear today, and that is pretty interesting. This is due to a rise in population and an evolution in technology, amongst other factors.

Technology has advanced, buildings have been built and cities have expanded greatly. This means that many major cities, monuments, and other popular sights have altered in appearance. Some of them might be familiar, and other places almost look unrecognizable.

The huge skyscrapers across New York were never there. All of the hustle and bustle in Vegas was once nonexistent. Some now-abandoned places were once busy and filled with life; some relics and monuments were once huge advancements in society. It's kind of scary and kind of amazing to see how much things change.

There are tons of photos online of cities, historical buildings, and other famous sights from the past compared to now. Here is a collection of 25 side-by-side photos of how places looked way in the past and how they look today.