No matter where you are coming from, Cairo or Alexandria, you have to pass through Marsa Matruh. Direct buses from Alexandria stop here for 30-40 min. on the way to Siwa and 'refill' the seats. This is the nearest big town near Siwa.
I am coming from Siwa and arrived here and found out that I am in shortage of 16 ELB to buy a ticket to Cairo. It happened perhaps dur to the high cost of desert safari I was ended up at paying. Since the local time 15,00 I was a little unsure if there would be any bank open. I tried to encash few dollars at a shopkeeper and asked if I can change some USD somewhere nearby. A local overheard my conversation (As usual, but this time it was saf perhaps because when he came to know I want to change only 20 USD (that was enough!) he called me a taxi and asked him to take to the town centre and ...coming up..
When I am done with my changing dollars all I wanted to do to take a taxi back to the bus statuion as soon as possible not to miss the last bus to Cairo and also to leave this place. They asked me take our photo. I did showed them their smiling faces and walked off soon.