Downtown
Columbia Center

Tallest public observation deck in seattle. Entrance is 15$. The views are fantastic!

https://www.tripadvisor.com/Attraction_Review-g60878-d143564-Reviews-Sky_View_Observatory-Seattle_Washington.html

Seattle Public Library

This library is massive. Offers a wide variety of spaces and services inside. Views of the city are great and the architecture of the library itself is fantastic. Only 2 blocks from Columbia Center. Worth checking out.

https://www.tripadvisor.com/Attraction_Review-g60878-d558679-Reviews-Seattle_Public_Library-Seattle_Washington.html

Smith Tower

The oldest sky-scraper in the city, it was once the tallest building west of the Mississippi. It held this distinction for 17 years from its completion in 1914 to 1931.

506 2nd Ave, Seattle, WA 98104

https://en.wikipedia.org/wiki/Smith_Tower

https://www.tripadvisor.com/Attraction_Review-g60878-d282644-Reviews-Smith_Tower_Chinese_Room_Observation_Deck-Seattle_Washington.html

Washington State Ferries

The Washington ferries system links the Seattle area on the east side of Puget Sound to towns on the Kitsap Peninsula and Olympic Peninsula and to British Columbia in Canada. If you have never ridden on a ferry, I would recommend riding one at least once during your visit. It's a pleasant way to travel and the scenery is spectacular! It's a unique experience for those who are from places where there is no ferry system.

http://www.wsdot.wa.gov/ferries/index.cfm

https://www.tripadvisor.com/Attraction_Review-g60878-d563102-Reviews-Washington_State_Ferries-Seattle_Washington.html

Seattle Aquarium

The Seattle Aquarium is on a pier over Elliot bay. They offer a wide variety of northwest aquatic life on display, including a 2-story floor-to-ceiling tank of amazing and colorful fish.

1483 Alaskan Way, Pier 59, Seattle, WA 98101

https://www.tripadvisor.com/Attraction_Review-g60878-d126554-Reviews-Seattle_Aquarium-Seattle_Washington.html

Capitol Hill
Roughly 1 mile to the east of pike place
Starbucks Reserve Roastery & Tasting Room

If you only visit one Starbucks while you are here, it should be this one. This is about as good as it gets when it comes to coffee. Sample coffee from around the world that was roasted right in front of you.

1124 Pike St, Seattle, WA 98101

https://www.tripadvisor.com/Attraction_Review-g60878-d7321281-Reviews-Starbucks_Reserve_Roastery_Tasting_Room-Seattle_Washington.html

North
Roughly 1-2 miles north of pike place: (walking distance – OR take the monorail)
Seattle Monorail

The monorail was built for the 1962 world's fair (along with the space needle). The cars and equipment have been maintained, but remain the same Alweg Rapid Transit vehicles built for the fair. The monorail now connects the Westlake light rail (subway) station with the Seattle center and space needle. Fare is $2.25 each way and only cash is accepted.

Westlake Center Station, at 5th Avenue and Pine Street

Seattle Center Station, adjacent to the Space Needle

http://www.seattlemonorail.com/

https://en.wikipedia.org/wiki/Seattle_Center_Monorail

Space Needle

1962, the Space Needle served as the symbol of that yearʹs Worldʹs Fair. It has since become the symbol of Seattle, and one of the most recognizable structures in the world.

400 Broad St Seattle, WA 98109 (206) 9052100

http://www.spaceneedle.com/

https://www.tripadvisor.com/Attraction_Review-g60878-d123109-Reviews-Space_Needle-Seattle_Washington.html

Experience Music Project

A groundbreaking place to truly take in the past, present, and future of music. With architecture that is daring to say the least, and music from the past and present taking center stage, Jimi Hendrix would be proud of the EMP, himself a native Seattleite.

325 5th Avenue North Seattle, WA 98109 (206) 7702702

http://www.empmuseum.org/index.asp

Pacific Science Center

The interactive exhibits and programs at the Pacific Science Center are for everyone, adults and kids alike.

206.437.1298 200 Second Avenue North Seattle, WA 98109 (206) 4432001

http://www.pacificsciencecenter.org/

https://www.tripadvisor.com/Attraction_Review-g60878-d3184389-Reviews-Chihuly_Garden_and_Glass-Seattle_Washington.html

Seattle Center

The home of the Space Needle, EMP, Pacific Science Center, Key Arena, KEXP Radio, Chihuly Glass, and more offers public lawns, fountains, a food court and other sites to take in or just take a break at.

https://www.tripadvisor.com/Attraction_Review-g60878-d143565-Reviews-Seattle_Center-Seattle_Washington.html

Ride the Ducks of Seattle

Tour Seattle by land and water on a WWII amphibious landing craft! Youʹll see all the sites of Seattle including the Seattle waterfront, Qwest Field, Safeco Field, historical Pioneer Square, Pike Place Market and the downtown shopping district! Then, head out to Fremont where youʹll SPLASH into Lake Union to see Gasworks Park, the Sleepless in Seattle floating home and a breath‐taking view of the Seattle skyline!

(206) 441 3825

http://www.ridetheducksofseattle.com/

MOHAI – Museum of History and Industry

The MOHAI catalogs the growth and history of the pacific northwest, including many companies and brands which started here as well as the history of the native population and settlers.

860 Terry Ave N, Seattle, WA 98109

mohai.org

https://www.tripadvisor.com/Attraction_Review-g60878-d141518-Reviews-Museum_of_History_Industry-Seattle_Washington.html

Kerry Park

Quite likely the best spot to take a photo of the city. It offers views of the space needle, skyline, and Mt Rainier in the background.

211 W Highland Dr, Seattle, WA 98119

http://www.tripadvisor.com/Attraction_Review-g60878-d1050677-Reviews-Kerry_Park-Seattle_Washington.html

Further to the north, accessible via Uber/Lyft/Transit are Fremont and Ballard:
GasWorks Park

GasWorks is a cleaned-up coal gasification plant that is now a public space with fantastic lake union views and northern views of the city. A place to just walk around in, or take a break on a blanket, its popular with people just looking to spend time outdoors.

2101 N Northlake Way, Seattle, WA 98103

https://www.tripadvisor.com/Attraction_Review-g60878-d141233-Reviews-Gas_Works_Park-Seattle_Washington.html

Fremont Troll

There is a troll made from an old Volkswagen beetle under a bridge. Yup, that's right. There is a huge concrete troll that is integrated with a car that watches over the water from under the Arora bridge.

3405 Troll Ave N, Seattle, WA 98103

https://www.tripadvisor.com/Attraction_Review-g60878-d183753-Reviews-Fremont_Troll-Seattle_Washington.html

Theo Chocolate Factory

If you have ever wanted to tour a chocolate factory, then this is your chance. In addition to getting a lot of history on cacao plants and sustainable farming, you will also see how this factory makes high quality crafted chocolates and will be offered plenty to taste as well. Their lobby / store alone offers free samples where you can visit and just about get sick on as much chocolate as you like.

3400 Phinney Ave N, Seattle, WA 98103

https://www.tripadvisor.com/Attraction_Review-g60878-d1066510-Reviews-Theo_Chocolate-Seattle_Washington.html

Hiram Chittenden Locks / Ballard Locks

The Ballard locks separate Puget Sound and the Admiralty Inlet from Lake Union / Lake Washington and sit at the end of a man-made waterway to connect the two. In addition to the magnificence of watching boats raise up and down, this location also offers under-water salmon ladder views as well as a wonderful garden to walk around in.

2899 NW 54th St, Seattle, WA 98107

https://www.tripadvisor.com/Attraction_Review-g60878-d319153-Reviews-Hiram_M_Chittenden_Locks-Seattle_Washington.html

Golden Gardens

Sitting on the edge of Puget Sound, this is one of two locations in Seattle (other is Alki Beach in West Seattle) which are public beaches. This place is VERY popular in the summer time with people enjoying the water, throwing footballs and Frisbees, or grilling out on the beach.

8498 Seaview Pl NW, Seattle, WA 98117

https://www.tripadvisor.com/Attraction_Review-g60878-d141229-Reviews-Golden_Gardens_Park-Seattle_Washington.html

North of Seattle is Everett / 45mins by car
Boeing Factory Tour

For those who REALLY want to see a functioning airplane factory up close and in person, Boeing offers regular tours of their functioning Everett plant where the 747 and 787 are assembled. Purchase tickets online in advance so you know which tour you are on, allow LOTS of travel time to get there, and an early warning: There are NO photographs allowed at all, no cameras, no PHONES, no electronics, no bags whatsoever. They are very serious about this rule and will take away anything you have. Just leave it locked in your car or pay for one of the lockers they have there.

8415 Paine Field Blvd, Mukilteo, WA 98275
http://futureofflight.org

https://www.tripadvisor.com/Attraction_Review-g58625-d150553-Reviews-Future_of_Flight_Aviation_Center_Boeing_Tour-Mukilteo_Washington.html

South
Roughly 1-2 miles south of pike place
Seattle Pinball Museum

508 Maynard Ave S, Seattle, WA 98104

seattlepinballmuseum.com

Century Link Field / Seattle Sounders

Home of the Seahawks and Sounders – They offer regular tours.

http://www.centurylinkfield.com/tour-centurylink-field/

Safeco Field / Seattle Mariners
Further to the south, accessible via Uber/Lyft/Transit are SoDo and Georgetown:
Georgetown Steam Plant – Will be open on Sat August 13th

Open the second Saturday of every month (free), the Georgetown steam plant is a trip back in time to one of Seattle's earliest electricity production using coal and boilers. The inside has been restored as much as possible in many places and is fascinating for those interested in engineering or literally steampunk.

6605 13th Ave S, Seattle, WA 98108

http://georgetownsteamplant.com/

Living Computer Museum

Showcasing a several functioning vintage computers and cataloging the industry's history

2245 1st Avenue South, Seattle, WA 98134

livingcomputermuseum.org

https://www.tripadvisor.com/Attraction_Review-g60878-d3655014-Reviews-Living_Computer_Museum-Seattle_Washington.html

Museum of Flight

Seattle's museum of flight showcases many early boeing plans, experimental craft, and historical planes as well such as a former airforce one, the first 747, a concord, and now also a NASA shuttle trainer.

9404 E Marginal Way S, Seattle, WA 98108

museumofflight.org

https://www.tripadvisor.com/Attraction_Review-g60878-d109350-Reviews-The_Museum_of_Flight-Seattle_Washington.html