Iga — or, more specifically, the town of Ueno (上野) within its borders — is best known as the birthplace of two famous people: haiku poet Matsuo Bashō (松尾芭蕉), the author of Narrow Road to the Deep North, and ninja clan leader Hanzō Hattori (服部半蔵), celebrated in fiction and found even in Quentin Tarantino's Kill Bill.
Iga is about halfway between Osaka and Nagoya, and about an hour and a half from Kyoto. The main stations are Iga-Kanbe (伊賀神戸駅), on the Kintetsu Osaka Line, and Iga-Ueno (伊賀上野), on the JR Kansai Main Line. The two stations are linked by the Kintetsu Iga Line, which takes you to Ueno-shi station (5 minutes, ¥220). The train windows may be adorned with solemn ninja pigs and triangular ninja heads, which can't help but stir up some excitement for what lies ahead.
From Osaka Take the subway to Tanimachi Kyu(9)chome Station. Walk east for 10 mins to Osaka Uehommachi Station (Kintensu Osaka line, a private railway line). The Local (普通 Futsū)(L) subway fare is the cheapest at 1110 Yen but takes 1.5 hours. The Limited Express (特急 Tokkyū) costs 1980 Yen but takes around 45 mins. Alight at Iga-Kanbe Station.
Iga Ninja Museum (9:00am-5:00pm, entry ¥700)  Ueno's top attraction by far, this old Japanese house was actually used by the Iga clan and is full of spiffy ninja secrets like trapdoors, revolving walls and more, all demonstrated by kunoichi - cheerful lady ninjas in pink garb. There is a museum on the grounds with good English displays, and there are also live demonstrations of ninja weaponry and techniques - hourly from 11 AM to 3 PM except Tuesdays (only weekends in Dec-Feb).
The Bashō Museum pays tribute to the haiku master Matsuo Bashō, who is thought to have been born in Iga. It's not often open, but the building itself, shaped like the hat Bashō wore, is a curious sight.
Ueno Castle (9:00am-5:00pm, closed December 29-31; admission ¥500) was a frequent target for ninja attacks in the old days. Resist the temptation to slip on a mask and go skulking around as if nobody can see you; the sleepy guard inside the castle doesn't need the hassle. It's one of the better-looking castle reconstructions in Japan, but the museum inside is not really worth a visit.
The Tenjin festival is held every year between October 23rd to 25th . Between the festivals the portable shrines are shown in the Danjiri Museum.