I think in general, 30 years old is an optimal age to get married for both (of course there are exceptions).

Once you have hit 30, you are probably mature enough to handle a relationship without silly insecurities. It means you have met enough people in your lifetime to be able to recognise a good soul. It means you have found a good balance between your brain and heart and won't let one dominate the other in your decision making. It means that you have lived long enough to have discovered yourself and what you want in a relationship without being influenced by others. It means you have lived long enough to have your own responsibilities and to establish yourself in the world and don't need anyone to support you. And last of all, it means you haven't lived long enough for you to have lost the childish delight that makes life so fun.