The dolls wear costumes from the Heian court period and the Empress doll is seated on the Emperor's right. Families pray for their daughters' growth before the Hina dolls.

There can be several tiers of dolls, but this varies. A single tier of 2 dolls is quite common. Japan has managed to hold on to these traditions while adopting many western traditions as well. In my 20 years living in Japan I have seen a dramatic rise in the celebration of Christmas (this in my opinion being driven and promoted by stores trying to shore up their profits), Easter, and Halloween. Japanese children (prior to 9/11) were allowed to come on the bases and participate in Halloween. Some bases still allow some children to come on the base. In all things Japanese, once adopted as a "custom" the Japanese tend to go all out so the kids often show up in halloween costumes that are nicer than the kids on base.

By the way, on March 8th the Yushima Tenjin cherry blossom festival starts. This shrine, in central Tokyo, has about 400 red and white cherry blossom trees dedicated to Sugawara Michizane, a great scholar of the 9th Century. This festival coincides with school entrance examinations so families and students come to the shrine and pray for success. The blossom season is short so you only have February and March to enjoy them.

March 14th is white day.
In Japan, Valentines day is where women give their special men some chocolate.
White day was created by a confectionary maker in 1965 as a way for men to reciprocate to their special lady for the gift given on Valentines day. It is called white day because the chocolate should be white. Originally, the gift was a marshmallow gift and the day was called Marshmallow day. Not a very attractive name in my opinion. Thus, eventually White day became the name.