Hercules is bordered by Draco to the north; Boötes, Corona Borealis, and Serpens Caput to the west; Ophiuchus to the south; Aquila to the southwest; and Sagitta, Vulpecula, and Lyra to the east.

[3] The official constellation boundaries, as set by Eugène Delporte in 1930, are defined by a polygon of 32 segments (illustrated in infobox).

[4] In mid-northern latitudes, Hercules is best observed from mid-spring until early autumn, culminating at midnight on June 13.

Alpha Herculis, traditionally called Rasalgethi, is a triple star system, partly resolvable in small amateur telescopes, 359 light-years from Earth.

[8] The secondary, a spectroscopic binary that orbits the primary every 3600 years, is a blue-green hued star of magnitude 5.6.

Zeta Herculis is a binary star that is becoming divisible in medium-aperture amateur telescopes, as the components widen to their peak in 2025.

Rho Herculis is a binary star 402 light-years from Earth, divisible in small amateur telescopes.

M13 lies between the stars η Her and ζ Her; it is dim, but may be detected by the unaided eye on a very clear night.

M13, visible to both the naked eye and binoculars, is a globular cluster of the 6th magnitude that contains more than 300,000 stars and is 25,200 light-years from Earth.

The oldest globular cluster known at 14 billion years, its stars are resolvable in a medium-aperture amateur telescope.

100,000 light-years from Earth, it is a Shapley class IV cluster, meaning that it is fairly rich in the center and quite concentrated at the nucleus.

[25] NGC 6210 is a planetary nebula of the 9th magnitude, 4000 light-years from Earth visible as a blue-green elliptical disk in amateur telescopes larger than 75 mm in aperture.

[31] Another bright radio source in Hercules is the quasar 3C 345 which has a jet that appears to move faster than the speed of light.

The hero's left leg contains dimmer stars of the fourth magnitude which do not have Bayer designations but which do have Flamsteed numbers.

White argues that this figure was, like the similarly named "Sitting Gods", depicted as a man with a serpent's body instead of legs (the serpent element now being represented on the Greek star map by the figure of Draco that Hercules crushes beneath his feet).

He further argues that the original name of Hercules – the 'Kneeler' (see below) – is a conflation of the two Babylonian constellations of the Sitting and Standing Gods.

Aratus describes it as follows: Right there in its [Draco's] orbit wheels a Phantom form, like to a man that strives at a task.

That sign no man knows how to read clearly, nor what task he is bent, but men simply call him On His Knees.

Here too that Crown [Corona], which glorious Dionysus set to be memorial of the dead Ariadne, wheels beneath the back of the toil-spent Phantom.

To the Phantom's back the Crown is near, but by his head mark near at hand the head of Ophiuchus [...] Yonder, too, is the tiny Tortoise, which, while still beside his cradle, Hermes pierced for strings and bade it be called the Lyre [Lyra]: and he brought it into heaven and set it in front of the unknown Phantom.