Yilan County officially has only one city - Yilan - although Luodong is where most businesses are located.
Yilan - the main city, with two big department stores, YouAi and Luna Plaza, National Yilan University, a big sports park, a decent cultural center, a small but tasty nightmarket, and some general great eats.
Jiaoxi - is known island-wide for its plentiful hot spring resorts. It's also home to some great hiking trails and waterfalls.
Toucheng - is a popular surfing destination. Offers spectacular sunrise views and is the disembarkation point for whale watching.
Yuanshan - has a nice little park that is heavily lanterned during the lantern festival.
Dian Song Pi Agricultural Leisure Area located in Sanshing township of Yilan county, between the Central and Shushang mountains that surround the Lanyang Plain. Because of its geographic location, the climate is fresh and the air is unpolluted . Additionally, this area has a wide range of temperatures, which fosters biodiversity. Tourists can observe hundreds of plants when walking in the area. Moreover, there are abundant natural resources such as fertile soil and abundant water, so the farmers in this area grow various unique agricultural products such as Sanshing green onions and pears. Residents have also developed rafting activities on the En-Nong river.
Yulan Agricultural Leisure Area - a famed tea producing region. Has great views of Lanyang Creek and is the entry point to Songluo Lake. A great place to appreciate cherry blossoms.
Take the North Railway Line (北迴鐵路) fast train (Zichang) to Toucheng, Yilan or Luodong Stations. Otherwise take the very slow (Putongche) to any of the other stations.
The quickest way from Taipei is on the Taipei-Yilan Freeway No.5 (北宜高速公路) south. It takes around 40 minutes on a good day.
Taxis outside the West Exit #4 of Taipei Main Station will take you to Yilan or Luodong for NT$ 300, but you can ask for a discount to NT$ 250. These taxis wait for 4 passengers before leaving (which is why the fare is so reasonable).
There are two buses, which are very nice and comfortable, that leave from Taipei and stop in Jiaosi, Yilan, and Luodong. Some buses are express/direct buses and don't stop at all stops so be sure to confirm your destination before boarding.
Capital Star -- Can be boarded on ZhongXiao East Road. It can be reached by going to the Taipei City Hall MRT stop. Take exit 3, keep walking straight ahead and you will see tents and attendants there to help you. You can purchase your ticket on site, as there are no reservations (it's good to arrive early because there is often a small line). Fare is NT$ 90 to Jiaosi, and NT$ 120 to Yilan or Luodong. Schedule is online 
Kamalan -- Can be boarded across the street from the Technology Building MRT stop on FuXing Rd, at the main bus station near Taipei Main Station, and at Banqiao bus station (near the Banqiao train station and MRT stop). You can make reservations and buy tickets ahead of time. Fares are to Jiaosi (105nt from Taipei, 129 from Banqiao), to Yilan (132 from Taipei, 155 from Banqiao), and to Luodong (136 from Taipei, 160 from Banqiao) Schedule is online 
As buses here are irregular and taxis are expensive, the best way to get around is by scooter. There are scooter rental shops near the train stations. Just remember to get a good map and that a driver's licence is required.
Yilan government has tried to improve its local transportation system to support the popular tourism. The various transportation to get to each popular tourist site is provided (traditional Chinese). The Capital Bus also serves the routes to many spots in Yilan County from Luodong .
Wufengchi Waterfalls - Yilan County's most famous waterfalls.
Annong Creek - white water rafting. Yilan's answer to Xiouguran river in Hualien County.
Fushan Botanical Garden - protected forest area. Permit required. Long waiting lists - especially for weekend visits.
Honeymoon Bay - Surfing Mecca.
Meihua Lake - a wonderful place to stroll and relax. Many B&B's nearby.
Taipingshan Forestry Recreation Area - a historic logging area and one of Taiwan's most scenic spots
Turtle Island - protected volcanic island. Great for whale watching. Permit required.
National Center for Traditional Arts, Wujie - a very large centre that preserves and promotes Taiwanese arts and culture. Features a recreated "old street" selling traditional crafts. Entry NT$ 150.
Lanyang Museum, a newly-established museum aimed at presenting Yilan’s overall geographical environment, cultural and humanistic trails. Entry NT$ 100 .
Bei Guan Leisure Farm,Toucheng - famous for its crab museum - with unique exibit of crabs that live in boiling volcanic springs.
He Dong Tang Lion Museum, Toucheng - a quaint little museum featuring numerous stone lion statues. Entry: NT$ 180.
Mary Leu Fine Art Carving Gallery, Sanshing - workshop and gallery for renowned artist Mary Leu. Entry: NT$ 100 - including coffee/tea.
Jia Zi Lan Wine Museum, Yilan - a historical distillery that also includes a small museum and gift shop. Entry: Free.
Museum of Yilan Government History, Yilan - a group of relics from the Japanese Colonial Era. Entry: NT$30 for the County Prefects House. Others are free.
Taiwanese Opera MuseumYilan - located in Yilan's Cultural Center, features exhibits on Traditional Chinese Opera and Puppets. With an id (passport or Taiwanese ID or ARC card) you can try on traditional opera clothing on the third floor.
Caoling Historic Trail - the only remaining hikable section of the ancient Tamalan Trail. Starts in Yuanwangken in Gongliao and finishes in Dali. Length: 8.5 Km.
Linmei Shipan Trail - extremely popular hiking trail in Jiaoxi. Some beautiful waterfalls. Length: 1.7 Km.
Marian Hiking Trail - breathtaking trail that starts behind the church at Wufengchi waterfalls in Jiaoxi. The trail is divided into two sections: The first, "winds its way gently through secondary growth forests for 3.7 Km - terminating 400 metres above sea level at the Tong Tien Bridge." The second section is decidedly more difficult. Although only 1.63 Km in length, the rough trail climbs steeply through dense, damp forests. In the last 300 metres, the forest gives way to windswept slopes covered in arrow bamboo and tall grasses. The final lookout - when not shrouded in mist - offers stunning views of the Lanyang plain and Turtle Island. The nearby St. Mary's Villa offers toilets and shelter.
Sinliao Waterfall Trail - stunning trail of moderate difficulty. Length: 2.3 Km - approximately 2 hours. Daily limit of 300 people. Photo ID required.
Dongshan Water Park (冬山河親水公園) -- an awesome water park which is a great place to visit during the sweltering summer days. It has various water activities (a giant slide, an octopus with a water-bed like surface underneath to slip and slide on, and an elevated surface with 'jumping' water jets) all complimented by techno music.
Luodong Nightmarket -- Many unique clothing stores nestled off the streets, along with lots of "famous" snack foods -- try the Lamb Soup, Baoxin Fenyuan (look for the douhua shop with the hearts on it), runbing (stir fried veggies with dried meat and shaved peanuts wrapped to look like a burrito in a thin, crepe-like wrapping), and ice cream with shaved peanut brittle and cilantro, wrapped in the same wrap as the runbing.