When choosing a vine, think about how much sun and water you have available. Ivy is nice for its evergreen characteristic but it requires shade. Also consider the size of a vine. Trumpetcreeper (Campsis radicans) and Wisteria both are beautiful in flower - although it will take years of growth before they actually push any flowers - but they need very strong support because they grow trunks as big as tree trunks and can lift fascia boards, tear off gutters, and knock over trellises. Grapes and Virginia Creeper (Parthenocissus quinquefolia) are tempting but because they are favorites of Japanese Beetles which plague Denver in July and August, we aren't recommending them at this point. There is a native Hops vine (Humulus lupulus) however, hops spread aggressively via underground roots so may not be the best choice if you have a small, urban garden.

If I were choosing, I'd look at Clematis, both spring flowering and fall flowering, and Honeysuckle (Lonicera) varieties. They are showy in flower but are easily managed because they can be cut back to the ground if they need to be renewed.

Here's a link to a short article from CSU Extension with additional information about vines for Colorado:
https://planttalk.colostate.edu/topics/trees-shrubs-vines/1727-vines-colorado/