The end of a (past) era: Apple doesn’t sell 30 pin adapters anymore.
Both the 30 pin to Lightning and the Micro-USB to 30 pin adapter have disappeared from Apple’s store. So if you have an iPhone 4s or older, you can’t buy these adapters from Apple anymore. However, the distribution might be quite high, so that you might still find one used.
But Apple doesn’t give up the support for the old 30 pin interface completely: there is still a USB-A to 30 pin cable to buy. So the connection possibilities for old equipment is still given.