Ipiales is a city close to the Ecuadorian border in Colombia. It is an obligatory stopover on your way to Ecuador. There is nothing much to see except the spectacular Iglesia de las Lajas.
The bus station is a bit out of town, but there are collectivos the center.
There are frequent buses to Pasto (1h30 - COP$15,000) and Popayan. Collectivos will bring you to Rumichaca for the border crossing if you go to Ecuador. The border crossing is quite easy and straightforward. The Colombian DAS-office is on one site of the bridge and the Ecuadorian office in on walking distance on the other side. From there are collectivos to Tulcán (0.75$). Don't sell your dollars on the border, the exchange rate is bad.
Cars from Ipiales to the frontier leave from the bus terminal and cost COP$1,500. They let you at the Colombian immigration control. After the formalities in both police controls, a minivan in the Ecuadorian side will take you to Tulcán for US$0.75. You can choose to get off at the city center or at the bus terminal.
The specialty is cuy (coo-ee), which is guinea pig. Best place to eat them is in the Carco barrio (outskirts of the town, heading to the Lajas church.)
Veggie option:
Wonderful Jugo bar just off the main Plaza to the north west -- try the Uvillo Completo (COP$3,000, and worth every penny) or the Alfalfa (COP$1,300). The "Completos" are made with honey, and the owners are friendly.
There are a lot of hotels near the bus terminal, e.g. Hotel San Jose: double for 50,000 COP with wifi and private bathroom.
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