The Romans got ideas for their architecture from other countries. They got many ideas from the Etruscans and the Greeks. The Romans changed things, though. They used a lot of arches, domes, and concrete.

Arches and domes were important. They made it possible to build a building with open space inside. Without arches and domes, a building had to be full of columns to hold up the roof. Concrete was also important. It was strong and cheap.

Romans liked arches. They built triumphal arches. These arches honored war victories. The Romans could also build a really big building using arches and concrete. They often put bricks or stone on the outside of the concrete to make it look better.

Some of the big buildings were apartments or temples. Some were basilicas. These were used for large indoor events. The biggest buildings were amphitheaters. These were used for gladiator games. They looked a bit like football stadiums. The best-known amphitheater is the Colosseum in Rome.

The Romans made improvements to their cities. They built aqueducts to bring water from far away. The Romans made sewers and roads. They built forums. A forum was a plaza. Each forum had shops and places to gather or make speeches.

Romans were also fond of public baths. A public bath was like a health club. It had pools for bathing and swimming. It also had exercise rooms, libraries, and theaters. A public bath could be very fancy.